2016-04-07 14:47:58

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 00/10] Use the ISA bus driver for PC/104 and ISA devices

This patchset is based on top of commit 3a3a5fece6f2 ("fs: kernfs: Replace
CURRENT_TIME by current_fs_time()") of the driver-core-next branch of the
driver-core repository.

Two new ISA bus driver macros are introduced in this patchset:
module_isa_driver and max_num_isa_dev.

The module_isa_driver macro is a helper macro for ISA drivers which do not
do anything special in module init/exit. This macro is modelled after the
module_pci_driver macro and eliminates a lot of module init/exit
boilerplate code.

The max_num_isa_dev macro is used to determine the maximum possible number
of ISA devices which may be registered in the I/O port address space given
the address extent of the ISA devices. This macro is useful for computing
the maximum number of elements necessary to hold the base addresses and
interrupt line numbers of ISA devices for the respective ISA driver.

Lacking other documentation, I often found myself repeatedly returning to
the commit message of the initial commit for drivers/base/isa.c authored by
Rene Herman. A verbatim copy of this commit message has been added to
Documentation/isa.txt, along with descriptions for the module_isa driver
and max_num_isa_dev macros, for posterity.

The Apex Embedded Systems STX104 may be used on 64-bit X86 systems. This
patchset allows the Apex Embedded Systems STX104 DAC driver to be compiled
for both 32-bit and 64-bit X86 systems by depending on the ISA_BUS
configuration option rather than the ISA configuration option.

Similarly, many PC/104 and ISA devices may also be used on 64-bit X86
systems. The platform driver had been used to enable support for these
devices on 64-bit X86 systems. With the introduction of the ISA_BUS
configuration option, the respective drivers for these devices may now
utilize the ISA bus driver without restricting support to only 32-bit X86
systems; the following drivers now utilize the ISA bus driver over the
platform driver:

* WinSystems EBC-C384 watchdog timer
* ACCES 104-DIO-48E GPIO driver
* ACCES 104-IDI-48 GPIO driver
* ACCES 104-IDIO-16 GPIO driver
* WinSystems WS16C48 GPIO driver

With the utilization of the ISA bus driver, the GPIO drivers in this
patchset may now support multiple devices for each of their respective ISA
drivers. A naming convention for module array parameters has been set based
on the Apex Embedded Systems STX104 DAC driver.

The "base" array module parameter sets the I/O port base address of each
device. The "irq" array module parameter sets the interrupt line number of
each device. Each element of the "base" array corresponds to a discrete
device; each element of the "irq" array corresponds to the respective
device addressed in the respective "base" array element.

William Breathitt Gray (10):
isa: Implement the module_isa_driver macro
isa: Implement the max_num_isa_dev macro
Documentation: Add ISA bus driver documentation
iio: stx104: Change STX104 dependency to ISA_BUS
iio: stx104: Utilize the module_isa_driver and max_num_isa_dev macros
watchdog: ebc-c384_wdt: Utilize the ISA bus driver
gpio: 104-dio-48e: Utilize the ISA bus driver
gpio: 104-idi-48: Utilize the ISA bus driver
gpio: 104-idio-16: Utilize the ISA bus driver
gpio: ws16c48: Utilize the ISA bus driver

Documentation/isa.txt | 121 ++++++++++++++++++++++++++++++++++++++++
MAINTAINERS | 5 ++
drivers/gpio/Kconfig | 38 +++++++------
drivers/gpio/gpio-104-dio-48e.c | 106 +++++++++++++----------------------
drivers/gpio/gpio-104-idi-48.c | 86 ++++++++++------------------
drivers/gpio/gpio-104-idio-16.c | 85 ++++++++++------------------
drivers/gpio/gpio-ws16c48.c | 88 ++++++++++-------------------
drivers/iio/dac/Kconfig | 2 +-
drivers/iio/dac/stx104.c | 24 +-------
drivers/watchdog/Kconfig | 2 +-
drivers/watchdog/ebc-c384_wdt.c | 43 ++++----------
include/linux/isa.h | 32 +++++++++++
12 files changed, 317 insertions(+), 315 deletions(-)
create mode 100644 Documentation/isa.txt

--
2.7.3


2016-04-07 14:48:10

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 01/10] isa: Implement the module_isa_driver macro

The module_isa_driver macro is a helper macro for ISA drivers which do
not do anything special in module init/exit. This eliminates a lot of
boilerplate code. Each module may only use this macro once, and calling
it replaces module_init and module_exit.

Signed-off-by: William Breathitt Gray <[email protected]>
---
include/linux/isa.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/include/linux/isa.h b/include/linux/isa.h
index 2a02862..d410259 100644
--- a/include/linux/isa.h
+++ b/include/linux/isa.h
@@ -36,4 +36,25 @@ static inline void isa_unregister_driver(struct isa_driver *d)
}
#endif

+/**
+ * module_isa_driver() - Helper macro for registering a ISA driver
+ * @__isa_driver: isa_driver struct
+ * @__num_isa_dev: number of devices to register
+ *
+ * Helper macro for ISA drivers which do not do anything special in module
+ * init/exit. This eliminates a lot of boilerplate code. Each module may only
+ * use this macro once, and calling it replaces module_init and module_exit.
+ */
+#define module_isa_driver(__isa_driver, __num_isa_dev) \
+static int __init __isa_driver##_init(void) \
+{ \
+ return isa_register_driver(&(__isa_driver), __num_isa_dev); \
+} \
+module_init(__isa_driver##_init); \
+static void __exit __isa_driver##_exit(void) \
+{ \
+ isa_unregister_driver(&(__isa_driver)); \
+} \
+module_exit(__isa_driver##_exit);
+
#endif /* __LINUX_ISA_H */
--
2.7.3

2016-04-07 14:48:34

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 03/10] Documentation: Add ISA bus driver documentation

This is a verbatim copy of the original commit message of the initial
commit of the ISA bus driver authored by Rene Herman. Descriptions of
the module_isa_driver macro and max_num_isa_dev macro are provided at
the end.

Signed-off-by: William Breathitt Gray <[email protected]>
---
Documentation/isa.txt | 121 ++++++++++++++++++++++++++++++++++++++++++++++++++
MAINTAINERS | 5 +++
2 files changed, 126 insertions(+)
create mode 100644 Documentation/isa.txt

diff --git a/Documentation/isa.txt b/Documentation/isa.txt
new file mode 100644
index 0000000..f232c26
--- /dev/null
+++ b/Documentation/isa.txt
@@ -0,0 +1,121 @@
+ISA Drivers
+-----------
+
+The following text is adapted from the commit message of the initial
+commit of the ISA bus driver authored by Rene Herman.
+
+During the recent "isa drivers using platform devices" discussion it was
+pointed out that (ALSA) ISA drivers ran into the problem of not having
+the option to fail driver load (device registration rather) upon not
+finding their hardware due to a probe() error not being passed up
+through the driver model. In the course of that, I suggested a separate
+ISA bus might be best; Russell King agreed and suggested this bus could
+use the .match() method for the actual device discovery.
+
+The attached does this. For this old non (generically) discoverable ISA
+hardware only the driver itself can do discovery so as a difference with
+the platform_bus, this isa_bus also distributes match() up to the
+driver.
+
+As another difference: these devices only exist in the driver model due
+to the driver creating them because it might want to drive them, meaning
+that all device creation has been made internal as well.
+
+The usage model this provides is nice, and has been acked from the ALSA
+side by Takashi Iwai and Jaroslav Kysela. The ALSA driver module_init's
+now (for oldisa-only drivers) become:
+
+static int __init alsa_card_foo_init(void)
+{
+ return isa_register_driver(&snd_foo_isa_driver, SNDRV_CARDS);
+}
+
+static void __exit alsa_card_foo_exit(void)
+{
+ isa_unregister_driver(&snd_foo_isa_driver);
+}
+
+Quite like the other bus models therefore. This removes a lot of
+duplicated init code from the ALSA ISA drivers.
+
+The passed in isa_driver struct is the regular driver struct embedding a
+struct device_driver, the normal probe/remove/shutdown/suspend/resume
+callbacks, and as indicated that .match callback.
+
+The "SNDRV_CARDS" you see being passed in is a "unsigned int ndev"
+parameter, indicating how many devices to create and call our methods
+with.
+
+The platform_driver callbacks are called with a platform_device param;
+the isa_driver callbacks are being called with a "struct device *dev,
+unsigned int id" pair directly -- with the device creation completely
+internal to the bus it's much cleaner to not leak isa_dev's by passing
+them in at all. The id is the only thing we ever want other then the
+struct device * anyways, and it makes for nicer code in the callbacks as
+well.
+
+With this additional .match() callback ISA drivers have all options. If
+ALSA would want to keep the old non-load behaviour, it could stick all
+of the old .probe in .match, which would only keep them registered after
+everything was found to be present and accounted for. If it wanted the
+behaviour of always loading as it inadvertently did for a bit after the
+changeover to platform devices, it could just not provide a .match() and
+do everything in .probe() as before.
+
+If it, as Takashi Iwai already suggested earlier as a way of following
+the model from saner buses more closely, wants to load when a later bind
+could conceivably succeed, it could use .match() for the prerequisites
+(such as checking the user wants the card enabled and that port/irq/dma
+values have been passed in) and .probe() for everything else. This is
+the nicest model.
+
+To the code...
+
+This exports only two functions; isa_{,un}register_driver().
+
+isa_register_driver() register's the struct device_driver, and then
+loops over the passed in ndev creating devices and registering them.
+This causes the bus match method to be called for them, which is:
+
+int isa_bus_match(struct device *dev, struct device_driver *driver)
+{
+ struct isa_driver *isa_driver = to_isa_driver(driver);
+
+ if (dev->platform_data == isa_driver) {
+ if (!isa_driver->match ||
+ isa_driver->match(dev, to_isa_dev(dev)->id))
+ return 1;
+ dev->platform_data = NULL;
+ }
+ return 0;
+}
+
+The first thing this does is check if this device is in fact one of this
+driver's devices by seeing if the device's platform_data pointer is set
+to this driver. Platform devices compare strings, but we don't need to
+do that with everything being internal, so isa_register_driver() abuses
+dev->platform_data as a isa_driver pointer which we can then check here.
+I believe platform_data is available for this, but if rather not, moving
+the isa_driver pointer to the private struct isa_dev is ofcourse fine as
+well.
+
+Then, if the the driver did not provide a .match, it matches. If it did,
+the driver match() method is called to determine a match.
+
+If it did _not_ match, dev->platform_data is reset to indicate this to
+isa_register_driver which can then unregister the device again.
+
+If during all this, there's any error, or no devices matched at all
+everything is backed out again and the error, or -ENODEV, is returned.
+
+isa_unregister_driver() just unregisters the matched devices and the
+driver itself.
+
+module_isa_driver is a helper macro for ISA drivers which do not do
+anything special in module init/exit. This eliminates a lot of
+boilerplate code. Each module may only use this macro once, and calling
+it replaces module_init and module_exit.
+
+max_num_isa_dev is a macro to determine the maximum possible number of
+ISA devices which may be registered in the I/O port address space given
+the address extent of the ISA devices.
diff --git a/MAINTAINERS b/MAINTAINERS
index 03e00c7..3713010 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5994,6 +5994,11 @@ F: include/linux/irqdomain.h
F: kernel/irq/irqdomain.c
F: kernel/irq/msi.c

+ISA
+M: William Breathitt Gray <[email protected]>
+S: Maintained
+F: Documentation/isa.txt
+
ISAPNP
M: Jaroslav Kysela <[email protected]>
S: Maintained
--
2.7.3

2016-04-07 14:48:38

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 05/10] iio: stx104: Utilize the module_isa_driver and max_num_isa_dev macros

The Apex Embedded Systems STX104 DAC drivers does not do anything
special in module init/exit. This patch eliminates the module init/exit
boilerplate code by utilizing the module_isa_driver macro.

Additionally, the max_num_isa_dev macro is utilized to simplify the
determination of maximum possible STX104 devices in the system.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/iio/dac/stx104.c | 24 +++---------------------
1 file changed, 3 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/dac/stx104.c b/drivers/iio/dac/stx104.c
index 174f4b7..2794122 100644
--- a/drivers/iio/dac/stx104.c
+++ b/drivers/iio/dac/stx104.c
@@ -33,16 +33,9 @@
}

#define STX104_EXTENT 16
-/**
- * The highest base address possible for an ISA device is 0x3FF; this results in
- * 1024 possible base addresses. Dividing the number of possible base addresses
- * by the address extent taken by each device results in the maximum number of
- * devices on a system.
- */
-#define MAX_NUM_STX104 (1024 / STX104_EXTENT)

-static unsigned base[MAX_NUM_STX104];
-static unsigned num_stx104;
+static unsigned int base[max_num_isa_dev(STX104_EXTENT)];
+static unsigned int num_stx104;
module_param_array(base, uint, &num_stx104, 0);
MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses");

@@ -134,18 +127,7 @@ static struct isa_driver stx104_driver = {
}
};

-static void __exit stx104_exit(void)
-{
- isa_unregister_driver(&stx104_driver);
-}
-
-static int __init stx104_init(void)
-{
- return isa_register_driver(&stx104_driver, num_stx104);
-}
-
-module_init(stx104_init);
-module_exit(stx104_exit);
+module_isa_driver(stx104_driver, num_stx104);

MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("Apex Embedded Systems STX104 DAC driver");
--
2.7.3

2016-04-07 14:48:45

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 06/10] watchdog: ebc-c384_wdt: Utilize the ISA bus driver

The WinSystems EBC-C384 watchdog timer is controlled via ISA bus
communication. As such, the ISA bus driver is more appropriate than the
platform driver for the WinSystems EBC-C384 watchdog timer driver.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/watchdog/Kconfig | 2 +-
drivers/watchdog/ebc-c384_wdt.c | 43 ++++++++++-------------------------------
2 files changed, 11 insertions(+), 34 deletions(-)

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index fb94765..b10761d 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -738,7 +738,7 @@ config ALIM7101_WDT

config EBC_C384_WDT
tristate "WinSystems EBC-C384 Watchdog Timer"
- depends on X86
+ depends on X86 && ISA_BUS
select WATCHDOG_CORE
help
Enables watchdog timer support for the watchdog timer on the
diff --git a/drivers/watchdog/ebc-c384_wdt.c b/drivers/watchdog/ebc-c384_wdt.c
index 77fda0b..4b849b8 100644
--- a/drivers/watchdog/ebc-c384_wdt.c
+++ b/drivers/watchdog/ebc-c384_wdt.c
@@ -16,10 +16,10 @@
#include <linux/errno.h>
#include <linux/io.h>
#include <linux/ioport.h>
+#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
#include <linux/types.h>
#include <linux/watchdog.h>

@@ -95,9 +95,8 @@ static const struct watchdog_info ebc_c384_wdt_info = {
.identity = MODULE_NAME
};

-static int __init ebc_c384_wdt_probe(struct platform_device *pdev)
+static int ebc_c384_wdt_probe(struct device *dev, unsigned int id)
{
- struct device *dev = &pdev->dev;
struct watchdog_device *wdd;

if (!devm_request_region(dev, BASE_ADDR, ADDR_EXTENT, dev_name(dev))) {
@@ -122,61 +121,39 @@ static int __init ebc_c384_wdt_probe(struct platform_device *pdev)
dev_warn(dev, "Invalid timeout (%u seconds), using default (%u seconds)\n",
timeout, WATCHDOG_TIMEOUT);

- platform_set_drvdata(pdev, wdd);
+ dev_set_drvdata(dev, wdd);

return watchdog_register_device(wdd);
}

-static int ebc_c384_wdt_remove(struct platform_device *pdev)
+static int ebc_c384_wdt_remove(struct device *dev, unsigned int id)
{
- struct watchdog_device *wdd = platform_get_drvdata(pdev);
+ struct watchdog_device *wdd = dev_get_drvdata(dev);

watchdog_unregister_device(wdd);

return 0;
}

-static struct platform_driver ebc_c384_wdt_driver = {
+static struct isa_driver ebc_c384_wdt_driver = {
+ .probe = ebc_c384_wdt_probe,
.driver = {
.name = MODULE_NAME
},
.remove = ebc_c384_wdt_remove
};

-static struct platform_device *ebc_c384_wdt_device;
-
static int __init ebc_c384_wdt_init(void)
{
- int err;
-
if (!dmi_match(DMI_BOARD_NAME, "EBC-C384 SBC"))
return -ENODEV;

- ebc_c384_wdt_device = platform_device_alloc(MODULE_NAME, -1);
- if (!ebc_c384_wdt_device)
- return -ENOMEM;
-
- err = platform_device_add(ebc_c384_wdt_device);
- if (err)
- goto err_platform_device;
-
- err = platform_driver_probe(&ebc_c384_wdt_driver, ebc_c384_wdt_probe);
- if (err)
- goto err_platform_driver;
-
- return 0;
-
-err_platform_driver:
- platform_device_del(ebc_c384_wdt_device);
-err_platform_device:
- platform_device_put(ebc_c384_wdt_device);
- return err;
+ return isa_register_driver(&ebc_c384_wdt_driver, 1);
}

static void __exit ebc_c384_wdt_exit(void)
{
- platform_device_unregister(ebc_c384_wdt_device);
- platform_driver_unregister(&ebc_c384_wdt_driver);
+ isa_unregister_driver(&ebc_c384_wdt_driver);
}

module_init(ebc_c384_wdt_init);
@@ -185,4 +162,4 @@ module_exit(ebc_c384_wdt_exit);
MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("WinSystems EBC-C384 watchdog timer driver");
MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("platform:" MODULE_NAME);
+MODULE_ALIAS("isa:" MODULE_NAME);
--
2.7.3

2016-04-07 14:48:54

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 07/10] gpio: 104-dio-48e: Utilize the ISA bus driver

The ACCES 104-DIO-48E series communicates via the ISA bus. As such, it
is more appropriate to use the ISA bus driver over the platform driver
to control the ACCES 104-DIO-48E GPIO driver.

This patch also adds support for multiple devices via the base and irq
module array parameters. Each element of the base array corresponds to a
discrete device; each element of the irq array corresponds to the
respective device addressed in the respective base array element.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/gpio/Kconfig | 9 ++--
drivers/gpio/gpio-104-dio-48e.c | 106 ++++++++++++++--------------------------
2 files changed, 43 insertions(+), 72 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 5f3429f..4ce3f8d 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -517,12 +517,13 @@ menu "Port-mapped I/O GPIO drivers"

config GPIO_104_DIO_48E
tristate "ACCES 104-DIO-48E GPIO support"
+ depends on ISA_BUS
select GPIOLIB_IRQCHIP
help
- Enables GPIO support for the ACCES 104-DIO-48E family. The base port
- address for the device may be configured via the dio_48e_base module
- parameter. The interrupt line number for the device may be configured
- via the dio_48e_irq module parameter.
+ Enables GPIO support for the ACCES 104-DIO-48E series (104-DIO-48E,
+ 104-DIO-24E). The base port addresses for the devices may be
+ configured via the base module parameter. The interrupt line numbers
+ for the devices may be configured via the irq module parameter.

config GPIO_104_IDIO_16
tristate "ACCES 104-IDIO-16 GPIO support"
diff --git a/drivers/gpio/gpio-104-dio-48e.c b/drivers/gpio/gpio-104-dio-48e.c
index 448a903..1a647c0 100644
--- a/drivers/gpio/gpio-104-dio-48e.c
+++ b/drivers/gpio/gpio-104-dio-48e.c
@@ -1,5 +1,5 @@
/*
- * GPIO driver for the ACCES 104-DIO-48E
+ * GPIO driver for the ACCES 104-DIO-48E series
* Copyright (C) 2016 William Breathitt Gray
*
* This program is free software; you can redistribute it and/or modify
@@ -10,6 +10,9 @@
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
+ *
+ * This driver supports the following ACCES devices: 104-DIO-48E and
+ * 104-DIO-24E.
*/
#include <linux/bitops.h>
#include <linux/device.h>
@@ -19,18 +22,23 @@
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
+#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
#include <linux/spinlock.h>

-static unsigned dio_48e_base;
-module_param(dio_48e_base, uint, 0);
-MODULE_PARM_DESC(dio_48e_base, "ACCES 104-DIO-48E base address");
-static unsigned dio_48e_irq;
-module_param(dio_48e_irq, uint, 0);
-MODULE_PARM_DESC(dio_48e_irq, "ACCES 104-DIO-48E interrupt line number");
+#define DIO48E_EXTENT 16
+#define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT)
+
+static unsigned int base[MAX_NUM_DIO48E];
+static unsigned int num_dio48e;
+module_param_array(base, uint, &num_dio48e, 0);
+MODULE_PARM_DESC(base, "ACCES 104-DIO-48E base addresses");
+
+static unsigned int irq[MAX_NUM_DIO48E];
+module_param_array(irq, uint, NULL, 0);
+MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers");

/**
* struct dio48e_gpio - GPIO device private data structure
@@ -294,23 +302,19 @@ static irqreturn_t dio48e_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static int __init dio48e_probe(struct platform_device *pdev)
+static int dio48e_probe(struct device *dev, unsigned int id)
{
- struct device *dev = &pdev->dev;
struct dio48e_gpio *dio48egpio;
- const unsigned base = dio_48e_base;
- const unsigned extent = 16;
const char *const name = dev_name(dev);
int err;
- const unsigned irq = dio_48e_irq;

dio48egpio = devm_kzalloc(dev, sizeof(*dio48egpio), GFP_KERNEL);
if (!dio48egpio)
return -ENOMEM;

- if (!devm_request_region(dev, base, extent, name)) {
+ if (!devm_request_region(dev, base[id], DIO48E_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
- base, base + extent);
+ base[id], base[id] + DIO48E_EXTENT);
return -EBUSY;
}

@@ -324,8 +328,8 @@ static int __init dio48e_probe(struct platform_device *pdev)
dio48egpio->chip.direction_output = dio48e_gpio_direction_output;
dio48egpio->chip.get = dio48e_gpio_get;
dio48egpio->chip.set = dio48e_gpio_set;
- dio48egpio->base = base;
- dio48egpio->irq = irq;
+ dio48egpio->base = base[id];
+ dio48egpio->irq = irq[id];

spin_lock_init(&dio48egpio->lock);

@@ -338,19 +342,19 @@ static int __init dio48e_probe(struct platform_device *pdev)
}

/* initialize all GPIO as output */
- outb(0x80, base + 3);
- outb(0x00, base);
- outb(0x00, base + 1);
- outb(0x00, base + 2);
- outb(0x00, base + 3);
- outb(0x80, base + 7);
- outb(0x00, base + 4);
- outb(0x00, base + 5);
- outb(0x00, base + 6);
- outb(0x00, base + 7);
+ outb(0x80, base[id] + 3);
+ outb(0x00, base[id]);
+ outb(0x00, base[id] + 1);
+ outb(0x00, base[id] + 2);
+ outb(0x00, base[id] + 3);
+ outb(0x80, base[id] + 7);
+ outb(0x00, base[id] + 4);
+ outb(0x00, base[id] + 5);
+ outb(0x00, base[id] + 6);
+ outb(0x00, base[id] + 7);

/* disable IRQ by default */
- inb(base + 0xB);
+ inb(base[id] + 0xB);

err = gpiochip_irqchip_add(&dio48egpio->chip, &dio48e_irqchip, 0,
handle_edge_irq, IRQ_TYPE_NONE);
@@ -359,7 +363,7 @@ static int __init dio48e_probe(struct platform_device *pdev)
goto err_gpiochip_remove;
}

- err = request_irq(irq, dio48e_irq_handler, 0, name, dio48egpio);
+ err = request_irq(irq[id], dio48e_irq_handler, 0, name, dio48egpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
goto err_gpiochip_remove;
@@ -372,9 +376,9 @@ err_gpiochip_remove:
return err;
}

-static int dio48e_remove(struct platform_device *pdev)
+static int dio48e_remove(struct device *dev, unsigned int id)
{
- struct dio48e_gpio *const dio48egpio = platform_get_drvdata(pdev);
+ struct dio48e_gpio *const dio48egpio = dev_get_drvdata(dev);

free_irq(dio48egpio->irq, dio48egpio);
gpiochip_remove(&dio48egpio->chip);
@@ -382,48 +386,14 @@ static int dio48e_remove(struct platform_device *pdev)
return 0;
}

-static struct platform_device *dio48e_device;
-
-static struct platform_driver dio48e_driver = {
+static struct isa_driver dio48e_driver = {
+ .probe = dio48e_probe,
.driver = {
.name = "104-dio-48e"
},
.remove = dio48e_remove
};
-
-static void __exit dio48e_exit(void)
-{
- platform_device_unregister(dio48e_device);
- platform_driver_unregister(&dio48e_driver);
-}
-
-static int __init dio48e_init(void)
-{
- int err;
-
- dio48e_device = platform_device_alloc(dio48e_driver.driver.name, -1);
- if (!dio48e_device)
- return -ENOMEM;
-
- err = platform_device_add(dio48e_device);
- if (err)
- goto err_platform_device;
-
- err = platform_driver_probe(&dio48e_driver, dio48e_probe);
- if (err)
- goto err_platform_driver;
-
- return 0;
-
-err_platform_driver:
- platform_device_del(dio48e_device);
-err_platform_device:
- platform_device_put(dio48e_device);
- return err;
-}
-
-module_init(dio48e_init);
-module_exit(dio48e_exit);
+module_isa_driver(dio48e_driver, num_dio48e);

MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver");
--
2.7.3

2016-04-07 14:48:58

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 08/10] gpio: 104-idi-48: Utilize the ISA bus driver

The ACCES 104-IDI-48 series communicates via the ISA bus. As such, it
is more appropriate to use the ISA bus driver over the platform driver
to control the ACCES 104-IDI-48 GPIO driver.

This patch also adds support for multiple devices via the base and irq
module array parameters. Each element of the base array corresponds to a
discrete device; each element of the irq array corresponds to the
respective device addressed in the respective base array element.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/gpio/Kconfig | 10 +++--
drivers/gpio/gpio-104-idi-48.c | 86 ++++++++++++++----------------------------
2 files changed, 34 insertions(+), 62 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 4ce3f8d..46db6fc 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -536,12 +536,14 @@ config GPIO_104_IDIO_16

config GPIO_104_IDI_48
tristate "ACCES 104-IDI-48 GPIO support"
+ depends on ISA_BUS
select GPIOLIB_IRQCHIP
help
- Enables GPIO support for the ACCES 104-IDI-48 family. The base port
- address for the device may be configured via the idi_48_base module
- parameter. The interrupt line number for the device may be configured
- via the idi_48_irq module parameter.
+ Enables GPIO support for the ACCES 104-IDI-48 family (104-IDI-48A,
+ 104-IDI-48AC, 104-IDI-48B, 104-IDI-48BC). The base port addresses for
+ the devices may be configured via the base module parameter. The
+ interrupt line numbers for the devices may be configured via the irq
+ module parameter.

config GPIO_F7188X
tristate "F71869, F71869A, F71882FG, F71889F and F81866 GPIO support"
diff --git a/drivers/gpio/gpio-104-idi-48.c b/drivers/gpio/gpio-104-idi-48.c
index e37cd4c..6c75c83 100644
--- a/drivers/gpio/gpio-104-idi-48.c
+++ b/drivers/gpio/gpio-104-idi-48.c
@@ -10,6 +10,9 @@
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
+ *
+ * This driver supports the following ACCES devices: 104-IDI-48A,
+ * 104-IDI-48AC, 104-IDI-48B, and 104-IDI-48BC.
*/
#include <linux/bitops.h>
#include <linux/device.h>
@@ -19,18 +22,23 @@
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
+#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
#include <linux/spinlock.h>

-static unsigned idi_48_base;
-module_param(idi_48_base, uint, 0);
-MODULE_PARM_DESC(idi_48_base, "ACCES 104-IDI-48 base address");
-static unsigned idi_48_irq;
-module_param(idi_48_irq, uint, 0);
-MODULE_PARM_DESC(idi_48_irq, "ACCES 104-IDI-48 interrupt line number");
+#define IDI_48_EXTENT 8
+#define MAX_NUM_IDI_48 max_num_isa_dev(IDI_48_EXTENT)
+
+static unsigned int base[MAX_NUM_IDI_48];
+static unsigned int num_idi_48;
+module_param_array(base, uint, &num_idi_48, 0);
+MODULE_PARM_DESC(base, "ACCES 104-IDI-48 base addresses");
+
+static unsigned int irq[MAX_NUM_IDI_48];
+module_param_array(irq, uint, NULL, 0);
+MODULE_PARM_DESC(irq, "ACCES 104-IDI-48 interrupt line numbers");

/**
* struct idi_48_gpio - GPIO device private data structure
@@ -211,23 +219,19 @@ static irqreturn_t idi_48_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static int __init idi_48_probe(struct platform_device *pdev)
+static int idi_48_probe(struct device *dev, unsigned int id)
{
- struct device *dev = &pdev->dev;
struct idi_48_gpio *idi48gpio;
- const unsigned base = idi_48_base;
- const unsigned extent = 8;
const char *const name = dev_name(dev);
int err;
- const unsigned irq = idi_48_irq;

idi48gpio = devm_kzalloc(dev, sizeof(*idi48gpio), GFP_KERNEL);
if (!idi48gpio)
return -ENOMEM;

- if (!devm_request_region(dev, base, extent, name)) {
+ if (!devm_request_region(dev, base[id], IDI_48_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
- base, base + extent);
+ base[id], base[id] + IDI_48_EXTENT);
return -EBUSY;
}

@@ -239,8 +243,8 @@ static int __init idi_48_probe(struct platform_device *pdev)
idi48gpio->chip.get_direction = idi_48_gpio_get_direction;
idi48gpio->chip.direction_input = idi_48_gpio_direction_input;
idi48gpio->chip.get = idi_48_gpio_get;
- idi48gpio->base = base;
- idi48gpio->irq = irq;
+ idi48gpio->base = base[id];
+ idi48gpio->irq = irq[id];

spin_lock_init(&idi48gpio->lock);

@@ -253,8 +257,8 @@ static int __init idi_48_probe(struct platform_device *pdev)
}

/* Disable IRQ by default */
- outb(0, base + 7);
- inb(base + 7);
+ outb(0, base[id] + 7);
+ inb(base[id] + 7);

err = gpiochip_irqchip_add(&idi48gpio->chip, &idi_48_irqchip, 0,
handle_edge_irq, IRQ_TYPE_NONE);
@@ -263,7 +267,7 @@ static int __init idi_48_probe(struct platform_device *pdev)
goto err_gpiochip_remove;
}

- err = request_irq(irq, idi_48_irq_handler, IRQF_SHARED, name,
+ err = request_irq(irq[id], idi_48_irq_handler, IRQF_SHARED, name,
idi48gpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
@@ -277,9 +281,9 @@ err_gpiochip_remove:
return err;
}

-static int idi_48_remove(struct platform_device *pdev)
+static int idi_48_remove(struct device *dev, unsigned int id)
{
- struct idi_48_gpio *const idi48gpio = platform_get_drvdata(pdev);
+ struct idi_48_gpio *const idi48gpio = dev_get_drvdata(dev);

free_irq(idi48gpio->irq, idi48gpio);
gpiochip_remove(&idi48gpio->chip);
@@ -287,48 +291,14 @@ static int idi_48_remove(struct platform_device *pdev)
return 0;
}

-static struct platform_device *idi_48_device;
-
-static struct platform_driver idi_48_driver = {
+static struct isa_driver idi_48_driver = {
+ .probe = idi_48_probe,
.driver = {
.name = "104-idi-48"
},
.remove = idi_48_remove
};
-
-static void __exit idi_48_exit(void)
-{
- platform_device_unregister(idi_48_device);
- platform_driver_unregister(&idi_48_driver);
-}
-
-static int __init idi_48_init(void)
-{
- int err;
-
- idi_48_device = platform_device_alloc(idi_48_driver.driver.name, -1);
- if (!idi_48_device)
- return -ENOMEM;
-
- err = platform_device_add(idi_48_device);
- if (err)
- goto err_platform_device;
-
- err = platform_driver_probe(&idi_48_driver, idi_48_probe);
- if (err)
- goto err_platform_driver;
-
- return 0;
-
-err_platform_driver:
- platform_device_del(idi_48_device);
-err_platform_device:
- platform_device_put(idi_48_device);
- return err;
-}
-
-module_init(idi_48_init);
-module_exit(idi_48_exit);
+module_isa_driver(idi_48_driver, num_idi_48);

MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("ACCES 104-IDI-48 GPIO driver");
--
2.7.3

2016-04-07 14:49:07

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 09/10] gpio: 104-idio-16: Utilize the ISA bus driver

The ACCES 104-IDIO-16 series communicates via the ISA bus. As such, it
is more appropriate to use the ISA bus driver over the platform driver
to control the ACCES 104-IDIO-16 GPIO driver.

This patch also adds support for multiple devices via the base and irq
module array parameters. Each element of the base array corresponds to a
discrete device; each element of the irq array corresponds to the
respective device addressed in the respective base array element.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/gpio/Kconfig | 10 +++--
drivers/gpio/gpio-104-idio-16.c | 85 ++++++++++++++---------------------------
2 files changed, 34 insertions(+), 61 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 46db6fc..5ee6706 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -527,12 +527,14 @@ config GPIO_104_DIO_48E

config GPIO_104_IDIO_16
tristate "ACCES 104-IDIO-16 GPIO support"
+ depends on ISA_BUS
select GPIOLIB_IRQCHIP
help
- Enables GPIO support for the ACCES 104-IDIO-16 family. The base port
- address for the device may be set via the idio_16_base module
- parameter. The interrupt line number for the device may be set via the
- idio_16_irq module parameter.
+ Enables GPIO support for the ACCES 104-IDIO-16 family (104-IDIO-16,
+ 104-IDIO-16E, 104-IDO-16, 104-IDIO-8, 104-IDIO-8E, 104-IDO-8). The
+ base port addresses for the devices may be configured via the base
+ module parameter. The interrupt line numbers for the devices may be
+ configured via the irq module parameter.

config GPIO_104_IDI_48
tristate "ACCES 104-IDI-48 GPIO support"
diff --git a/drivers/gpio/gpio-104-idio-16.c b/drivers/gpio/gpio-104-idio-16.c
index ecc85fe..6787b8f 100644
--- a/drivers/gpio/gpio-104-idio-16.c
+++ b/drivers/gpio/gpio-104-idio-16.c
@@ -10,6 +10,9 @@
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
+ *
+ * This driver supports the following ACCES devices: 104-IDIO-16,
+ * 104-IDIO-16E, 104-IDO-16, 104-IDIO-8, 104-IDIO-8E, and 104-IDO-8.
*/
#include <linux/bitops.h>
#include <linux/device.h>
@@ -19,18 +22,23 @@
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
+#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
#include <linux/spinlock.h>

-static unsigned idio_16_base;
-module_param(idio_16_base, uint, 0);
-MODULE_PARM_DESC(idio_16_base, "ACCES 104-IDIO-16 base address");
-static unsigned idio_16_irq;
-module_param(idio_16_irq, uint, 0);
-MODULE_PARM_DESC(idio_16_irq, "ACCES 104-IDIO-16 interrupt line number");
+#define IDIO_16_EXTENT 8
+#define MAX_NUM_IDIO_16 max_num_isa_dev(IDIO_16_EXTENT)
+
+static unsigned int base[MAX_NUM_IDIO_16];
+static unsigned int num_idio_16;
+module_param_array(base, uint, &num_idio_16, 0);
+MODULE_PARM_DESC(base, "ACCES 104-IDIO-16 base addresses");
+
+static unsigned int irq[MAX_NUM_IDIO_16];
+module_param_array(irq, uint, NULL, 0);
+MODULE_PARM_DESC(irq, "ACCES 104-IDIO-16 interrupt line numbers");

/**
* struct idio_16_gpio - GPIO device private data structure
@@ -185,23 +193,19 @@ static irqreturn_t idio_16_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static int __init idio_16_probe(struct platform_device *pdev)
+static int idio_16_probe(struct device *dev, unsigned int id)
{
- struct device *dev = &pdev->dev;
struct idio_16_gpio *idio16gpio;
- const unsigned base = idio_16_base;
- const unsigned extent = 8;
const char *const name = dev_name(dev);
int err;
- const unsigned irq = idio_16_irq;

idio16gpio = devm_kzalloc(dev, sizeof(*idio16gpio), GFP_KERNEL);
if (!idio16gpio)
return -ENOMEM;

- if (!devm_request_region(dev, base, extent, name)) {
+ if (!devm_request_region(dev, base[id], IDIO_16_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
- base, base + extent);
+ base[id], base[id] + IDIO_16_EXTENT);
return -EBUSY;
}

@@ -215,8 +219,8 @@ static int __init idio_16_probe(struct platform_device *pdev)
idio16gpio->chip.direction_output = idio_16_gpio_direction_output;
idio16gpio->chip.get = idio_16_gpio_get;
idio16gpio->chip.set = idio_16_gpio_set;
- idio16gpio->base = base;
- idio16gpio->irq = irq;
+ idio16gpio->base = base[id];
+ idio16gpio->irq = irq[id];
idio16gpio->out_state = 0xFFFF;

spin_lock_init(&idio16gpio->lock);
@@ -230,8 +234,8 @@ static int __init idio_16_probe(struct platform_device *pdev)
}

/* Disable IRQ by default */
- outb(0, base + 2);
- outb(0, base + 1);
+ outb(0, base[id] + 2);
+ outb(0, base[id] + 1);

err = gpiochip_irqchip_add(&idio16gpio->chip, &idio_16_irqchip, 0,
handle_edge_irq, IRQ_TYPE_NONE);
@@ -240,7 +244,7 @@ static int __init idio_16_probe(struct platform_device *pdev)
goto err_gpiochip_remove;
}

- err = request_irq(irq, idio_16_irq_handler, 0, name, idio16gpio);
+ err = request_irq(irq[id], idio_16_irq_handler, 0, name, idio16gpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
goto err_gpiochip_remove;
@@ -253,9 +257,9 @@ err_gpiochip_remove:
return err;
}

-static int idio_16_remove(struct platform_device *pdev)
+static int idio_16_remove(struct device *dev, unsigned int id)
{
- struct idio_16_gpio *const idio16gpio = platform_get_drvdata(pdev);
+ struct idio_16_gpio *const idio16gpio = dev_get_drvdata(dev);

free_irq(idio16gpio->irq, idio16gpio);
gpiochip_remove(&idio16gpio->chip);
@@ -263,48 +267,15 @@ static int idio_16_remove(struct platform_device *pdev)
return 0;
}

-static struct platform_device *idio_16_device;
-
-static struct platform_driver idio_16_driver = {
+static struct isa_driver idio_16_driver = {
+ .probe = idio_16_probe,
.driver = {
.name = "104-idio-16"
},
.remove = idio_16_remove
};

-static void __exit idio_16_exit(void)
-{
- platform_device_unregister(idio_16_device);
- platform_driver_unregister(&idio_16_driver);
-}
-
-static int __init idio_16_init(void)
-{
- int err;
-
- idio_16_device = platform_device_alloc(idio_16_driver.driver.name, -1);
- if (!idio_16_device)
- return -ENOMEM;
-
- err = platform_device_add(idio_16_device);
- if (err)
- goto err_platform_device;
-
- err = platform_driver_probe(&idio_16_driver, idio_16_probe);
- if (err)
- goto err_platform_driver;
-
- return 0;
-
-err_platform_driver:
- platform_device_del(idio_16_device);
-err_platform_device:
- platform_device_put(idio_16_device);
- return err;
-}
-
-module_init(idio_16_init);
-module_exit(idio_16_exit);
+module_isa_driver(idio_16_driver, num_idio_16);

MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("ACCES 104-IDIO-16 GPIO driver");
--
2.7.3

2016-04-07 14:49:13

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 10/10] gpio: ws16c48: Utilize the ISA bus driver

The WinSystems WS16C48 communicates via the ISA bus. As such, it is more
appropriate to use the ISA bus driver over the platform driver to
control the WinSystems WS16C48 GPIO driver.

This patch also adds support for multiple devices via the base and irq
module array parameters. Each element of the base array corresponds to a
discrete device; each element of the irq array corresponds to the
respective device addressed in the respective base array element.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/gpio/Kconfig | 9 ++---
drivers/gpio/gpio-ws16c48.c | 88 +++++++++++++++------------------------------
2 files changed, 33 insertions(+), 64 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 5ee6706..25f2553 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -614,12 +614,13 @@ config GPIO_TS5500

config GPIO_WS16C48
tristate "WinSystems WS16C48 GPIO support"
+ depends on ISA_BUS
select GPIOLIB_IRQCHIP
help
- Enables GPIO support for the WinSystems WS16C48. The base port address
- for the device may be configured via the ws16c48_base module
- parameter. The interrupt line number for the device may be configured
- via the ws16c48_irq module parameter.
+ Enables GPIO support for the WinSystems WS16C48. The base port
+ addresses for the devices may be configured via the base module
+ parameter. The interrupt line numbers for the devices may be
+ configured via the irq module parameter.

endmenu

diff --git a/drivers/gpio/gpio-ws16c48.c b/drivers/gpio/gpio-ws16c48.c
index 51f41e8..eaa71d4 100644
--- a/drivers/gpio/gpio-ws16c48.c
+++ b/drivers/gpio/gpio-ws16c48.c
@@ -19,18 +19,23 @@
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
+#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
#include <linux/spinlock.h>

-static unsigned ws16c48_base;
-module_param(ws16c48_base, uint, 0);
-MODULE_PARM_DESC(ws16c48_base, "WinSystems WS16C48 base address");
-static unsigned ws16c48_irq;
-module_param(ws16c48_irq, uint, 0);
-MODULE_PARM_DESC(ws16c48_irq, "WinSystems WS16C48 interrupt line number");
+#define WS16C48_EXTENT 16
+#define MAX_NUM_WS16C48 max_num_isa_dev(WS16C48_EXTENT)
+
+static unsigned int base[MAX_NUM_WS16C48];
+static unsigned int num_ws16c48;
+module_param_array(base, uint, &num_ws16c48, 0);
+MODULE_PARM_DESC(base, "WinSystems WS16C48 base addresses");
+
+static unsigned int irq[MAX_NUM_WS16C48];
+module_param_array(irq, uint, NULL, 0);
+MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers");

/**
* struct ws16c48_gpio - GPIO device private data structure
@@ -298,23 +303,19 @@ static irqreturn_t ws16c48_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static int __init ws16c48_probe(struct platform_device *pdev)
+static int ws16c48_probe(struct device *dev, unsigned int id)
{
- struct device *dev = &pdev->dev;
struct ws16c48_gpio *ws16c48gpio;
- const unsigned base = ws16c48_base;
- const unsigned extent = 16;
const char *const name = dev_name(dev);
int err;
- const unsigned irq = ws16c48_irq;

ws16c48gpio = devm_kzalloc(dev, sizeof(*ws16c48gpio), GFP_KERNEL);
if (!ws16c48gpio)
return -ENOMEM;

- if (!devm_request_region(dev, base, extent, name)) {
+ if (!devm_request_region(dev, base[id], WS16C48_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
- base, base + extent);
+ base[id], base[id] + WS16C48_EXTENT);
return -EBUSY;
}

@@ -328,8 +329,8 @@ static int __init ws16c48_probe(struct platform_device *pdev)
ws16c48gpio->chip.direction_output = ws16c48_gpio_direction_output;
ws16c48gpio->chip.get = ws16c48_gpio_get;
ws16c48gpio->chip.set = ws16c48_gpio_set;
- ws16c48gpio->base = base;
- ws16c48gpio->irq = irq;
+ ws16c48gpio->base = base[id];
+ ws16c48gpio->irq = irq[id];

spin_lock_init(&ws16c48gpio->lock);

@@ -342,11 +343,11 @@ static int __init ws16c48_probe(struct platform_device *pdev)
}

/* Disable IRQ by default */
- outb(0x80, base + 7);
- outb(0, base + 8);
- outb(0, base + 9);
- outb(0, base + 10);
- outb(0xC0, base + 7);
+ outb(0x80, base[id] + 7);
+ outb(0, base[id] + 8);
+ outb(0, base[id] + 9);
+ outb(0, base[id] + 10);
+ outb(0xC0, base[id] + 7);

err = gpiochip_irqchip_add(&ws16c48gpio->chip, &ws16c48_irqchip, 0,
handle_edge_irq, IRQ_TYPE_NONE);
@@ -355,7 +356,7 @@ static int __init ws16c48_probe(struct platform_device *pdev)
goto err_gpiochip_remove;
}

- err = request_irq(irq, ws16c48_irq_handler, IRQF_SHARED, name,
+ err = request_irq(irq[id], ws16c48_irq_handler, IRQF_SHARED, name,
ws16c48gpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
@@ -369,9 +370,9 @@ err_gpiochip_remove:
return err;
}

-static int ws16c48_remove(struct platform_device *pdev)
+static int ws16c48_remove(struct device *dev, unsigned int id)
{
- struct ws16c48_gpio *const ws16c48gpio = platform_get_drvdata(pdev);
+ struct ws16c48_gpio *const ws16c48gpio = dev_get_drvdata(dev);

free_irq(ws16c48gpio->irq, ws16c48gpio);
gpiochip_remove(&ws16c48gpio->chip);
@@ -379,48 +380,15 @@ static int ws16c48_remove(struct platform_device *pdev)
return 0;
}

-static struct platform_device *ws16c48_device;
-
-static struct platform_driver ws16c48_driver = {
+static struct isa_driver ws16c48_driver = {
+ .probe = ws16c48_probe,
.driver = {
.name = "ws16c48"
},
.remove = ws16c48_remove
};

-static void __exit ws16c48_exit(void)
-{
- platform_device_unregister(ws16c48_device);
- platform_driver_unregister(&ws16c48_driver);
-}
-
-static int __init ws16c48_init(void)
-{
- int err;
-
- ws16c48_device = platform_device_alloc(ws16c48_driver.driver.name, -1);
- if (!ws16c48_device)
- return -ENOMEM;
-
- err = platform_device_add(ws16c48_device);
- if (err)
- goto err_platform_device;
-
- err = platform_driver_probe(&ws16c48_driver, ws16c48_probe);
- if (err)
- goto err_platform_driver;
-
- return 0;
-
-err_platform_driver:
- platform_device_del(ws16c48_device);
-err_platform_device:
- platform_device_put(ws16c48_device);
- return err;
-}
-
-module_init(ws16c48_init);
-module_exit(ws16c48_exit);
+module_isa_driver(ws16c48_driver, num_ws16c48);

MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("WinSystems WS16C48 GPIO driver");
--
2.7.3

2016-04-07 14:48:31

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

The Apex Embedded Systems STX104 may be used on 64-bit X86 systems. This
patch allows the Apex Embedded Systems STX104 DAC driver to be compiled
for both 32-bit and 64-bit X86 systems.

Signed-off-by: William Breathitt Gray <[email protected]>
---
drivers/iio/dac/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index a995139..df4b55d 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -210,7 +210,7 @@ config MCP4922

config STX104
tristate "Apex Embedded Systems STX104 DAC driver"
- depends on ISA
+ depends on X86 && ISA_BUS
help
Say yes here to build support for the 2-channel DAC on the Apex
Embedded Systems STX104 integrated analog PC/104 card. The base port
--
2.7.3

2016-04-07 14:48:18

by William Breathitt Gray

[permalink] [raw]
Subject: [PATCH 02/10] isa: Implement the max_num_isa_dev macro

max_num_isa_dev is a macro to determine the maximum possible number of
ISA devices which may be registered in the I/O port address space given
the address extent of the ISA devices.

The highest base address possible for an ISA device is 0x3FF; this
results in 1024 possible base addresses. Dividing the number of possible
base addresses by the address extent taken by each device results in the
maximum number of devices on a system.

Signed-off-by: William Breathitt Gray <[email protected]>
---
include/linux/isa.h | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/include/linux/isa.h b/include/linux/isa.h
index d410259..bc0a7c0 100644
--- a/include/linux/isa.h
+++ b/include/linux/isa.h
@@ -57,4 +57,15 @@ static void __exit __isa_driver##_exit(void) \
} \
module_exit(__isa_driver##_exit);

+/**
+ * max_num_isa_dev() - Maximum possible number registered of an ISA device
+ * @__ida_dev_ext: ISA device address extent
+ *
+ * The highest base address possible for an ISA device is 0x3FF; this results in
+ * 1024 possible base addresses. Dividing the number of possible base addresses
+ * by the address extent taken by each device results in the maximum number of
+ * devices on a system.
+ */
+#define max_num_isa_dev(__isa_dev_ext) (1024 / __isa_dev_ext)
+
#endif /* __LINUX_ISA_H */
--
2.7.3

2016-04-08 00:35:46

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH 06/10] watchdog: ebc-c384_wdt: Utilize the ISA bus driver

On Thu, Apr 07, 2016 at 10:47:27AM -0400, William Breathitt Gray wrote:
> The WinSystems EBC-C384 watchdog timer is controlled via ISA bus
> communication. As such, the ISA bus driver is more appropriate than the
> platform driver for the WinSystems EBC-C384 watchdog timer driver.
>
> Signed-off-by: William Breathitt Gray <[email protected]>
> ---
> drivers/watchdog/Kconfig | 2 +-
> drivers/watchdog/ebc-c384_wdt.c | 43 ++++++++++-------------------------------
> 2 files changed, 11 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index fb94765..b10761d 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -738,7 +738,7 @@ config ALIM7101_WDT
>
> config EBC_C384_WDT
> tristate "WinSystems EBC-C384 Watchdog Timer"
> - depends on X86
> + depends on X86 && ISA_BUS

I am a bit concerend that the newly introduced ISA_BUS is not automatically
enabled. Effectively this means that all drivers depending on it will
be disabled until someone enables ISA_BUS in the distribution.

Is this a concern for anyone but me ?

Anyway, since you are the driver maintainer, I assume that you are ok
with it, so

Acked-by: Guenter Roeck <[email protected]>

Side note for Wim: ISA_BUS was introduced with commit b3c1be1b789c
("base: isa: Remove X86_32 dependency") in -next.

Guenter

> select WATCHDOG_CORE
> help
> Enables watchdog timer support for the watchdog timer on the
> diff --git a/drivers/watchdog/ebc-c384_wdt.c b/drivers/watchdog/ebc-c384_wdt.c
> index 77fda0b..4b849b8 100644
> --- a/drivers/watchdog/ebc-c384_wdt.c
> +++ b/drivers/watchdog/ebc-c384_wdt.c
> @@ -16,10 +16,10 @@
> #include <linux/errno.h>
> #include <linux/io.h>
> #include <linux/ioport.h>
> +#include <linux/isa.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/moduleparam.h>
> -#include <linux/platform_device.h>
> #include <linux/types.h>
> #include <linux/watchdog.h>
>
> @@ -95,9 +95,8 @@ static const struct watchdog_info ebc_c384_wdt_info = {
> .identity = MODULE_NAME
> };
>
> -static int __init ebc_c384_wdt_probe(struct platform_device *pdev)
> +static int ebc_c384_wdt_probe(struct device *dev, unsigned int id)
> {
> - struct device *dev = &pdev->dev;
> struct watchdog_device *wdd;
>
> if (!devm_request_region(dev, BASE_ADDR, ADDR_EXTENT, dev_name(dev))) {
> @@ -122,61 +121,39 @@ static int __init ebc_c384_wdt_probe(struct platform_device *pdev)
> dev_warn(dev, "Invalid timeout (%u seconds), using default (%u seconds)\n",
> timeout, WATCHDOG_TIMEOUT);
>
> - platform_set_drvdata(pdev, wdd);
> + dev_set_drvdata(dev, wdd);
>
> return watchdog_register_device(wdd);
> }
>
> -static int ebc_c384_wdt_remove(struct platform_device *pdev)
> +static int ebc_c384_wdt_remove(struct device *dev, unsigned int id)
> {
> - struct watchdog_device *wdd = platform_get_drvdata(pdev);
> + struct watchdog_device *wdd = dev_get_drvdata(dev);
>
> watchdog_unregister_device(wdd);
>
> return 0;
> }
>
> -static struct platform_driver ebc_c384_wdt_driver = {
> +static struct isa_driver ebc_c384_wdt_driver = {
> + .probe = ebc_c384_wdt_probe,
> .driver = {
> .name = MODULE_NAME
> },
> .remove = ebc_c384_wdt_remove
> };
>
> -static struct platform_device *ebc_c384_wdt_device;
> -
> static int __init ebc_c384_wdt_init(void)
> {
> - int err;
> -
> if (!dmi_match(DMI_BOARD_NAME, "EBC-C384 SBC"))
> return -ENODEV;
>
> - ebc_c384_wdt_device = platform_device_alloc(MODULE_NAME, -1);
> - if (!ebc_c384_wdt_device)
> - return -ENOMEM;
> -
> - err = platform_device_add(ebc_c384_wdt_device);
> - if (err)
> - goto err_platform_device;
> -
> - err = platform_driver_probe(&ebc_c384_wdt_driver, ebc_c384_wdt_probe);
> - if (err)
> - goto err_platform_driver;
> -
> - return 0;
> -
> -err_platform_driver:
> - platform_device_del(ebc_c384_wdt_device);
> -err_platform_device:
> - platform_device_put(ebc_c384_wdt_device);
> - return err;
> + return isa_register_driver(&ebc_c384_wdt_driver, 1);
> }
>
> static void __exit ebc_c384_wdt_exit(void)
> {
> - platform_device_unregister(ebc_c384_wdt_device);
> - platform_driver_unregister(&ebc_c384_wdt_driver);
> + isa_unregister_driver(&ebc_c384_wdt_driver);
> }
>
> module_init(ebc_c384_wdt_init);
> @@ -185,4 +162,4 @@ module_exit(ebc_c384_wdt_exit);
> MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
> MODULE_DESCRIPTION("WinSystems EBC-C384 watchdog timer driver");
> MODULE_LICENSE("GPL v2");
> -MODULE_ALIAS("platform:" MODULE_NAME);
> +MODULE_ALIAS("isa:" MODULE_NAME);
> --
> 2.7.3
>

2016-04-08 00:45:04

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On Thu, Apr 07, 2016 at 10:47:25AM -0400, William Breathitt Gray wrote:
> The Apex Embedded Systems STX104 may be used on 64-bit X86 systems. This
> patch allows the Apex Embedded Systems STX104 DAC driver to be compiled
> for both 32-bit and 64-bit X86 systems.
>
> Signed-off-by: William Breathitt Gray <[email protected]>
> ---
> drivers/iio/dac/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
> index a995139..df4b55d 100644
> --- a/drivers/iio/dac/Kconfig
> +++ b/drivers/iio/dac/Kconfig
> @@ -210,7 +210,7 @@ config MCP4922
>
> config STX104
> tristate "Apex Embedded Systems STX104 DAC driver"
> - depends on ISA
> + depends on X86 && ISA_BUS

This means for this and other similar drivers that the driver is no longer
supported on architectures which support ISA but not the newly introduced
ISA_BUS. Affected architectures are alpha, arm, m32r, m68k, mips, powerpc,
and parisc.

A typical example is SCSI_AHA1542, which is no longer supported on those
architectures. It builds, but isa_register_driver() will be a dummy and fail.
Actually, this is true for _all_ drivers calling isa_register_driver().

I hope this is understood and doesn't cause any problems.

Thanks,
Guenter

> help
> Say yes here to build support for the 2-channel DAC on the Apex
> Embedded Systems STX104 integrated analog PC/104 card. The base port
> --
> 2.7.3
>

2016-04-08 12:03:55

by William Breathitt Gray

[permalink] [raw]
Subject: Re: [PATCH 06/10] watchdog: ebc-c384_wdt: Utilize the ISA bus driver

On Thu, Apr 07, 2016 at 05:35:35PM -0700, Guenter Roeck wrote:
>I am a bit concerend that the newly introduced ISA_BUS is not automatically
>enabled. Effectively this means that all drivers depending on it will
>be disabled until someone enables ISA_BUS in the distribution.
>
>Is this a concern for anyone but me ?
>
>Anyway, since you are the driver maintainer, I assume that you are ok
>with it, so
>
>Acked-by: Guenter Roeck <[email protected]>
>
>Side note for Wim: ISA_BUS was introduced with commit b3c1be1b789c
>("base: isa: Remove X86_32 dependency") in -next.
>
>Guenter

Since the ISA bus lacks standardized probing functionality, and the
majority of ISA devices I've encountered expect the user to start
writing to the device's I/O port addresses from the get-go, I think
ISA_BUS should remain an explicit dependency rather than become selected
when a user chooses a driver. That is to say, it is more appropriate for
a user to explicitly enable ISA_BUS if their system has an ISA bus;
otherwise a user may enable a driver with the expectation of a device
probe, whereas the driver will simply start writing to I/O port
addresses unexpectedly.

William Breathitt Gray

2016-04-08 12:32:07

by William Breathitt Gray

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On Thu, Apr 07, 2016 at 05:45:03PM -0700, Guenter Roeck wrote:
>This means for this and other similar drivers that the driver is no longer
>supported on architectures which support ISA but not the newly introduced
>ISA_BUS. Affected architectures are alpha, arm, m32r, m68k, mips, powerpc,
>and parisc.
>
>A typical example is SCSI_AHA1542, which is no longer supported on those
>architectures. It builds, but isa_register_driver() will be a dummy and fail.
>Actually, this is true for _all_ drivers calling isa_register_driver().
>
>I hope this is understood and doesn't cause any problems.
>
>Thanks,
>Guenter

That's a good catch. I overlooked this when I submitted the ISA_BUS
patch; I had improperly assumed the ISA option to have a dependency on
X86_32 based on arch/x86/Kconfig. The intention of the ISA_BUS is to
allow the proper definition of the isa_register_driver and
isa_unregister_driver functions without the dependency on X86_32 (e.g.
on X86_64 systems). How can this be resolved without ending support for
ISA on these other architectures? Would it be appropriate to add the
ISA_BUS dependency to every "config ISA" block for the other
architectures?

My avoidance of making ISA a selection of ISA_BUS is the possibility of
an invalid configuration: a user may initially enable ISA_BUS, then
later disable ISA, resulting in ISA_BUS remaining enabled without ISA
selected.

As a side note, should the dummy isa_register_driver return 0? Would it
be more appropriate for it to return an error code to indicate lack of
support for ISA, rather than silently fail?

William Breathitt Gray

2016-04-08 13:18:13

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On 04/08/2016 05:31 AM, William Breathitt Gray wrote:
> On Thu, Apr 07, 2016 at 05:45:03PM -0700, Guenter Roeck wrote:
>> This means for this and other similar drivers that the driver is no longer
>> supported on architectures which support ISA but not the newly introduced
>> ISA_BUS. Affected architectures are alpha, arm, m32r, m68k, mips, powerpc,
>> and parisc.
>>
>> A typical example is SCSI_AHA1542, which is no longer supported on those
>> architectures. It builds, but isa_register_driver() will be a dummy and fail.
>> Actually, this is true for _all_ drivers calling isa_register_driver().
>>
>> I hope this is understood and doesn't cause any problems.
>>
>> Thanks,
>> Guenter
>
> That's a good catch. I overlooked this when I submitted the ISA_BUS
> patch; I had improperly assumed the ISA option to have a dependency on
> X86_32 based on arch/x86/Kconfig. The intention of the ISA_BUS is to
> allow the proper definition of the isa_register_driver and
> isa_unregister_driver functions without the dependency on X86_32 (e.g.
> on X86_64 systems). How can this be resolved without ending support for
> ISA on these other architectures? Would it be appropriate to add the
> ISA_BUS dependency to every "config ISA" block for the other
> architectures?
>
From the context, arm and mips use "select ISA". For those, adding and
auto-selecting ISA_BUS would make sense. For the remaining architectures
you could simply add "config ISA_BUS". I would suggest to update default
configurations, though.

There is also "um", for which you effectively disabled ISA support
as far as I can see. You might want to look into that as well.

> My avoidance of making ISA a selection of ISA_BUS is the possibility of
> an invalid configuration: a user may initially enable ISA_BUS, then
> later disable ISA, resulting in ISA_BUS remaining enabled without ISA
> selected.
>
Does that even make sense ? Not sure I understand why you don't just
select ISA_BUS if ISA is selected. That would also be backward compatible
and avoid the problem I was concerned about.

> As a side note, should the dummy isa_register_driver return 0? Would it
> be more appropriate for it to return an error code to indicate lack of
> support for ISA, rather than silently fail?
>
One should think so.

Thanks,
Guenter

2016-04-08 15:09:38

by William Breathitt Gray

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On Fri, Apr 08, 2016 at 06:18:09AM -0700, Guenter Roeck wrote:
> From the context, arm and mips use "select ISA". For those, adding and
>auto-selecting ISA_BUS would make sense. For the remaining architectures
>you could simply add "config ISA_BUS". I would suggest to update default
>configurations, though.
>
>There is also "um", for which you effectively disabled ISA support
>as far as I can see. You might want to look into that as well.
>
>> My avoidance of making ISA a selection of ISA_BUS is the possibility of
>> an invalid configuration: a user may initially enable ISA_BUS, then
>> later disable ISA, resulting in ISA_BUS remaining enabled without ISA
>> selected.
>>
>Does that even make sense ? Not sure I understand why you don't just
>select ISA_BUS if ISA is selected. That would also be backward compatible
>and avoid the problem I was concerned about.

I feel now that the introduction of the ISA_BUS option may the wrong
approach to resolve lack of ISA support for the X86_64 architecture;
adding ISA_BUS depends or selects through various Kconfigs would simply
obfuscate the ISA option. The true issue is that various driver
configs are assuming X86_32 architecture when they depend on the ISA
option, but the ISA bus does not require an X86_32 architecture.

The proper resolution then is to remove the misguided ISA_BUS option and
move the X86_32 dependency to the relevant drivers configs explicitly.
A grep for isa_register_driver calls within the kernel reveals that only
a few drivers explicitly use it. It should be trivial to create a patch
to add the explicit X86_32 dependency to the relevant drivers, so I will
submit one soon when I get the time to decouple X86_32 from the ISA
config option.

Once ISA is freed from the X86_32 dependency, I will simply use it
instead of ISA_BUS, and rebase this patchset for version 2.

>> As a side note, should the dummy isa_register_driver return 0? Would it
>> be more appropriate for it to return an error code to indicate lack of
>> support for ISA, rather than silently fail?
>>
>One should think so.
>
>Thanks,
>Guenter
>

I'll submit a separate patch for this as well then.

William Breathitt Gray

2016-04-08 18:28:04

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On Fri, Apr 08, 2016 at 11:09:22AM -0400, William Breathitt Gray wrote:
> On Fri, Apr 08, 2016 at 06:18:09AM -0700, Guenter Roeck wrote:
> > From the context, arm and mips use "select ISA". For those, adding and
> >auto-selecting ISA_BUS would make sense. For the remaining architectures
> >you could simply add "config ISA_BUS". I would suggest to update default
> >configurations, though.
> >
> >There is also "um", for which you effectively disabled ISA support
> >as far as I can see. You might want to look into that as well.
> >
> >> My avoidance of making ISA a selection of ISA_BUS is the possibility of
> >> an invalid configuration: a user may initially enable ISA_BUS, then
> >> later disable ISA, resulting in ISA_BUS remaining enabled without ISA
> >> selected.
> >>
> >Does that even make sense ? Not sure I understand why you don't just
> >select ISA_BUS if ISA is selected. That would also be backward compatible
> >and avoid the problem I was concerned about.
>
> I feel now that the introduction of the ISA_BUS option may the wrong
> approach to resolve lack of ISA support for the X86_64 architecture;
> adding ISA_BUS depends or selects through various Kconfigs would simply
> obfuscate the ISA option. The true issue is that various driver
> configs are assuming X86_32 architecture when they depend on the ISA
> option, but the ISA bus does not require an X86_32 architecture.
>
> The proper resolution then is to remove the misguided ISA_BUS option and
> move the X86_32 dependency to the relevant drivers configs explicitly.
> A grep for isa_register_driver calls within the kernel reveals that only
> a few drivers explicitly use it. It should be trivial to create a patch
> to add the explicit X86_32 dependency to the relevant drivers, so I will
> submit one soon when I get the time to decouple X86_32 from the ISA
> config option.
>

That might be tricky: At least some if not many of those drivers are expected
to run on non-X86 architectures, and thus don't really depend on X86_32
(possibly some depend on 32 bit - I didn't check).

I count 44 calls to isa_register_driver() in the current mainline.
Not sure if this counts as "only a few drivers".

Thanks,
Guenter

> Once ISA is freed from the X86_32 dependency, I will simply use it
> instead of ISA_BUS, and rebase this patchset for version 2.
>
> >> As a side note, should the dummy isa_register_driver return 0? Would it
> >> be more appropriate for it to return an error code to indicate lack of
> >> support for ISA, rather than silently fail?
> >>
> >One should think so.
> >
> >Thanks,
> >Guenter
> >
>
> I'll submit a separate patch for this as well then.
>
> William Breathitt Gray
> --
> To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html

2016-04-08 19:27:35

by William Breathitt Gray

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On Fri, Apr 08, 2016 at 11:28:01AM -0700, Guenter Roeck wrote:
>On Fri, Apr 08, 2016 at 11:09:22AM -0400, William Breathitt Gray wrote:
>> I feel now that the introduction of the ISA_BUS option may the wrong
>> approach to resolve lack of ISA support for the X86_64 architecture;
>> adding ISA_BUS depends or selects through various Kconfigs would simply
>> obfuscate the ISA option. The true issue is that various driver
>> configs are assuming X86_32 architecture when they depend on the ISA
>> option, but the ISA bus does not require an X86_32 architecture.
>>
>> The proper resolution then is to remove the misguided ISA_BUS option and
>> move the X86_32 dependency to the relevant drivers configs explicitly.
>> A grep for isa_register_driver calls within the kernel reveals that only
>> a few drivers explicitly use it. It should be trivial to create a patch
>> to add the explicit X86_32 dependency to the relevant drivers, so I will
>> submit one soon when I get the time to decouple X86_32 from the ISA
>> config option.
>>
>
>That might be tricky: At least some if not many of those drivers are expected
>to run on non-X86 architectures, and thus don't really depend on X86_32
>(possibly some depend on 32 bit - I didn't check).
>
>I count 44 calls to isa_register_driver() in the current mainline.
>Not sure if this counts as "only a few drivers".
>
>Thanks,
>Guenter

You're right, I there are more drivers that call isa_register_driver
than I had estimated. I think a different approach may work however.

When I initially proposed a patch to decouple the X86_32 dependency from
the ISA config option, I received a reply from the 0-DAY kernel test
auto-build indicating the errors from the drivers assuming a X86_32
architecture
(http://www.gossamer-threads.com/lists/linux/kernel/2350122#2350122).
After reviewing the debug messages, I realized there are only four main
issues:

1. sound/isa/sscape.c:594:14:
snd_printk format uses '%d' but a size_t is passed in
2. arch/x86/mm/extable.c:23:15:
'SEGMENT_IS_PNP_CODE' is undeclared
3. drivers/pnp/pnpbios/bioscall.c:
a slew of undeclared symbols and casting type mismatches
4. drivers/scsi/ultrastor.c:674:29:
sprintf format uses '%05X' but a kernel pointer is passed in

Both issue 1 and issue 4 are easily fixed by patching the respective
lines to match the format string with the variable type and vice-versa.

Issue 2 and 3 are the actual X86_32 assumption I had suspected: these
files depend on symbols declared in the include/asm/segment.h file; the
declaration of these symbols is conditional: #ifdef CONFIG_X86_32.

I believe this is the source of the issues I encountered on my initial
attempt to decouple the X86_32 dependency from the ISA option. I suspect
if I add an explicit X86_32 dependency to the PNPBIOS driver, I will be
able to remove the X86_32 dependency from the ISA option without
incident from the other drivers.

William Breathitt Gray

2016-04-09 12:59:34

by Alan Cox

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

> I believe this is the source of the issues I encountered on my initial
> attempt to decouple the X86_32 dependency from the ISA option. I suspect
> if I add an explicit X86_32 dependency to the PNPBIOS driver, I will be
> able to remove the X86_32 dependency from the ISA option without
> incident from the other drivers.

That would be correct. PnPBIOS is obsoleted by ACPI so a 64bit x86
platform shouldn't be using PnPBIOS nor anything non x86. Strictly
speaking PnpBIOS is not ISA, it's onboard devices.

ISA devices that can be enumerated are usually enumerated via ISAPnP
which is platform independent.

Quite a few of the ISA drivers if you review them more carefully have
other endian and size assumptions, IRQ assumptions and probably fun bugs
because they've simply never been run on anything else even when it is
possible.

Alan

2016-04-09 13:51:03

by William Breathitt Gray

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

On Sat, Apr 09, 2016 at 01:58:14PM +0100, One Thousand Gnomes wrote:
>> I believe this is the source of the issues I encountered on my initial
>> attempt to decouple the X86_32 dependency from the ISA option. I suspect
>> if I add an explicit X86_32 dependency to the PNPBIOS driver, I will be
>> able to remove the X86_32 dependency from the ISA option without
>> incident from the other drivers.
>
>That would be correct. PnPBIOS is obsoleted by ACPI so a 64bit x86
>platform shouldn't be using PnPBIOS nor anything non x86. Strictly
>speaking PnpBIOS is not ISA, it's onboard devices.
>
>ISA devices that can be enumerated are usually enumerated via ISAPnP
>which is platform independent.
>
>Quite a few of the ISA drivers if you review them more carefully have
>other endian and size assumptions, IRQ assumptions and probably fun bugs
>because they've simply never been run on anything else even when it is
>possible.
>
>Alan

It looks like I'm in quite a pickle. Even if the patch for the PnPBIOS
driver removes the errors and warnings, there may be runtime bugs in
other drivers expecting X86_32. The only way I can see to prevent that
is to audit all the drivers which depend on the ISA option -- a behemoth
undertaking which would be far too impractical and error-prone for me to
do.

The alternative then is to do as Guenter Roeck suggests and
introduce/select ISA_BUS in the various other architectures which lack
it. In this scenario, I would expect the ISA option to be avoided for
new drivers, wherefore the ISA_BUS option can be used regardless of
architecture configuration.

I would prefer for a single ISA configuration option, but not at the
expense on breaking existing drivers; therefore, I will work instead on
adding the necessary ISA_BUS code to the various areas which require
them. If there are problems with this plan too, let me know.

William Breathitt Gray

2016-04-09 15:52:51

by Alan Cox

[permalink] [raw]
Subject: Re: [PATCH 04/10] iio: stx104: Change STX104 dependency to ISA_BUS

> It looks like I'm in quite a pickle. Even if the patch for the PnPBIOS
> driver removes the errors and warnings, there may be runtime bugs in
> other drivers expecting X86_32. The only way I can see to prevent that
> is to audit all the drivers which depend on the ISA option -- a behemoth
> undertaking which would be far too impractical and error-prone for me to
> do.

I actually wouldn't worry. We've got lots of other drivers that don't
work on all the platforms they should because nobody has ever tried them
out.

At least if they compile on the different platforms people will be able
to try them. It's not making anything any worse - it used to not work and
it still doesn't work is the failure case 8)

Alan

2016-04-11 06:59:16

by Linus Walleij

[permalink] [raw]
Subject: Re: [PATCH 00/10] Use the ISA bus driver for PC/104 and ISA devices

On Thu, Apr 7, 2016 at 4:47 PM, William Breathitt Gray
<[email protected]> wrote:

> Two new ISA bus driver macros are introduced in this patchset:
> module_isa_driver and max_num_isa_dev.
(...)
> gpio: 104-dio-48e: Utilize the ISA bus driver
> gpio: 104-idi-48: Utilize the ISA bus driver
> gpio: 104-idio-16: Utilize the ISA bus driver
> gpio: ws16c48: Utilize the ISA bus driver

For these:
Acked-by: Linus Walleij <[email protected]>

So if the driver core maintainers want to merge this as part
of the series, go ahead.

Yours,
Linus Walleij