2022-08-24 14:45:23

by Kumaravel Thiagarajan

[permalink] [raw]
Subject: [PATCH v1 char-misc-next 2/5] misc: microchip: pci1xxxx: load gpio driver for the gpio controller auxiliary device enumerated by the auxiliary bus driver.

PIO function's auxiliary bus driver enumerates separate child devices for
GPIO controller and OTP/EEPROM interface. This gpio driver implemented
based on the gpio framework is loaded for the gpio auxiliary device.

Signed-off-by: Kumaravel Thiagarajan <[email protected]>
---
MAINTAINERS | 1 +
drivers/misc/mchp_pci1xxxx/Makefile | 2 +-
.../misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c | 163 ++++++++++++++++++
3 files changed, 165 insertions(+), 1 deletion(-)
create mode 100644 drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 9d20c9af0d5c..d90cfd74fe81 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13250,6 +13250,7 @@ L: [email protected]
S: Supported
F: drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.c
F: drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gp.h
+F: drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c

MICROCHIP OTPC DRIVER
M: Claudiu Beznea <[email protected]>
diff --git a/drivers/misc/mchp_pci1xxxx/Makefile b/drivers/misc/mchp_pci1xxxx/Makefile
index 23927ab251c4..fc4615cfe28b 100644
--- a/drivers/misc/mchp_pci1xxxx/Makefile
+++ b/drivers/misc/mchp_pci1xxxx/Makefile
@@ -1 +1 @@
-obj-$(CONFIG_GP_PCI1XXXX) := mchp_pci1xxxx_gp.o
+obj-$(CONFIG_GP_PCI1XXXX) := mchp_pci1xxxx_gp.o mchp_pci1xxxx_gpio.o
diff --git a/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c
new file mode 100644
index 000000000000..97ed7ae1baaa
--- /dev/null
+++ b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2022 Microchip Technology Inc.
+// pci1xxxx gpio driver
+
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/gpio/driver.h>
+#include <linux/bio.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/kthread.h>
+
+#include "mchp_pci1xxxx_gp.h"
+
+#define PCI1XXXX_NR_PINS 93
+#define PULLUP_OFFSET(x) ((((x) / 32) * 4) + 0x400 + 0x40)
+#define PULLDOWN_OFFSET(x) ((((x) / 32) * 4) + 0x400 + 0x50)
+#define OPENDRAIN_OFFSET(x) ((((x) / 32) * 4) + 0x400 + 0x60)
+#define DEBOUNCE_OFFSET(x) ((((x) / 32) * 4) + 0x400 + 0xE0)
+#define PIO_GLOBAL_CONFIG_OFFSET (0x400 + 0xF0)
+#define PIO_PCI_CTRL_REG_OFFSET (0x400 + 0xF4)
+#define INTR_MASK_OFFSET(x) ((((x) / 32) * 4) + 0x400 + 0x100)
+#define INTR_STATUS_OFFSET(x) (((x) * 4) + 0x400 + 0xD0)
+
+struct pci1xxxx_gpio {
+ struct auxiliary_device *aux_dev;
+ void __iomem *reg_base;
+ struct gpio_chip gpio;
+ spinlock_t lock;
+ int irq_base;
+};
+
+static inline void pci1xxx_assign_bit(void __iomem *base_addr, unsigned int reg_offset,
+ unsigned int bitpos, bool set)
+{
+ u32 data;
+
+ data = readl(base_addr + reg_offset);
+ if (set)
+ data |= BIT(bitpos);
+ else
+ data &= ~BIT(bitpos);
+ writel(data, base_addr + reg_offset);
+}
+
+static int pci1xxxx_gpio_set_config(struct gpio_chip *gpio, unsigned int offset,
+ unsigned long config)
+{
+ struct pci1xxxx_gpio *priv = gpiochip_get_data(gpio);
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ switch (pinconf_to_config_param(config)) {
+ case PIN_CONFIG_BIAS_PULL_UP:
+ pci1xxx_assign_bit(priv->reg_base, PULLUP_OFFSET(offset), (offset % 32), true);
+ break;
+ case PIN_CONFIG_BIAS_PULL_DOWN:
+ pci1xxx_assign_bit(priv->reg_base, PULLDOWN_OFFSET(offset), (offset % 32), true);
+ break;
+ case PIN_CONFIG_BIAS_DISABLE:
+ pci1xxx_assign_bit(priv->reg_base, PULLUP_OFFSET(offset), (offset % 32), false);
+ pci1xxx_assign_bit(priv->reg_base, PULLDOWN_OFFSET(offset), (offset % 32), false);
+ break;
+ case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+ pci1xxx_assign_bit(priv->reg_base, OPENDRAIN_OFFSET(offset), (offset % 32), true);
+ break;
+ default:
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ret;
+}
+
+static int pci1xxxx_gpio_setup(struct pci1xxxx_gpio *priv, int irq)
+{
+ struct gpio_chip *gchip = &priv->gpio;
+
+ gchip->label = dev_name(&priv->aux_dev->dev);
+ gchip->parent = &priv->aux_dev->dev;
+ gchip->owner = THIS_MODULE;
+ gchip->set_config = pci1xxxx_gpio_set_config;
+ gchip->dbg_show = NULL;
+ gchip->base = -1;
+ gchip->ngpio = PCI1XXXX_NR_PINS;
+ gchip->can_sleep = false;
+
+ return 0;
+}
+
+static int pci1xxxx_gpio_probe(struct auxiliary_device *aux_dev,
+ const struct auxiliary_device_id *id)
+
+{
+ struct auxiliary_device_wrapper *aux_dev_wrapper;
+ struct gp_aux_data_type *pdata;
+ struct pci1xxxx_gpio *priv;
+ int retval;
+
+ aux_dev_wrapper = (struct auxiliary_device_wrapper *)
+ container_of(aux_dev, struct auxiliary_device_wrapper, aux_dev);
+
+ pdata = &aux_dev_wrapper->gp_aux_data;
+
+ if (!pdata)
+ return -EINVAL;
+
+ priv = devm_kzalloc(&aux_dev->dev, sizeof(struct pci1xxxx_gpio), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->aux_dev = aux_dev;
+
+ if (!devm_request_mem_region(&aux_dev->dev, pdata->region_start, 0x800, aux_dev->name))
+ return -EBUSY;
+
+ priv->reg_base = devm_ioremap(&aux_dev->dev, pdata->region_start, 0x800);
+ if (!priv->reg_base)
+ return -ENOMEM;
+
+ writel(0x0264, (priv->reg_base + 0x400 + 0xF0));
+
+ retval = pci1xxxx_gpio_setup(priv, pdata->irq_num);
+
+ if (retval < 0)
+ return retval;
+
+ dev_set_drvdata(&aux_dev->dev, priv);
+
+ return devm_gpiochip_add_data(&aux_dev->dev, &priv->gpio, priv);
+}
+
+const struct auxiliary_device_id pci1xxxx_gpio_auxiliary_id_table[] = {
+ {.name = "mchp_pci1xxxx_gp.gp_gpio"},
+ {}
+};
+
+static struct auxiliary_driver pci1xxxx_gpio_driver = {
+ .driver = {
+ .name = "PCI1xxxxGPIO",
+ },
+ .probe = pci1xxxx_gpio_probe,
+ .id_table = pci1xxxx_gpio_auxiliary_id_table
+};
+
+static int __init pci1xxxx_gpio_driver_init(void)
+{
+ return auxiliary_driver_register(&pci1xxxx_gpio_driver);
+}
+
+static void __exit pci1xxxx_gpio_driver_exit(void)
+{
+ auxiliary_driver_unregister(&pci1xxxx_gpio_driver);
+}
+
+module_init(pci1xxxx_gpio_driver_init);
+module_exit(pci1xxxx_gpio_driver_exit);
+
+MODULE_DESCRIPTION("Microchip Technology Inc. PCI1xxxx GPIO controller");
+MODULE_AUTHOR("Kumaravel Thiagarajan <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.25.1


2023-02-17 10:31:33

by Michael Walle

[permalink] [raw]
Subject: Re: [PATCH v1 char-misc-next 2/5] misc: microchip: pci1xxxx: load gpio driver for the gpio controller auxiliary device enumerated by the auxiliary bus driver.

[+ GPIO maintainers]

> PIO function's auxiliary bus driver enumerates separate child devices for
> GPIO controller and OTP/EEPROM interface. This gpio driver implemented
> based on the gpio framework is loaded for the gpio auxiliary device.
>
> Signed-off-by: Kumaravel Thiagarajan <[email protected]>
> ---
> MAINTAINERS | 1 +
> drivers/misc/mchp_pci1xxxx/Makefile | 2 +-
> .../misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c | 163 ++++++++++++++++++

Why doesn't this file live in the GPIO subsystem? Seems like this haven't
got a proper review from the GPIO people (probably due to the "misc:"
subject). Maybe even GPIO_REGMAP could be used.

-michael

2023-02-23 10:24:51

by Linus Walleij

[permalink] [raw]
Subject: Re: [PATCH v1 char-misc-next 2/5] misc: microchip: pci1xxxx: load gpio driver for the gpio controller auxiliary device enumerated by the auxiliary bus driver.

On Fri, Feb 17, 2023 at 11:31 AM Michael Walle <[email protected]> wrote:
> [+ GPIO maintainers]
>
> > PIO function's auxiliary bus driver enumerates separate child devices for
> > GPIO controller and OTP/EEPROM interface. This gpio driver implemented
> > based on the gpio framework is loaded for the gpio auxiliary device.
> >
> > Signed-off-by: Kumaravel Thiagarajan <[email protected]>
> > ---
> > MAINTAINERS | 1 +
> > drivers/misc/mchp_pci1xxxx/Makefile | 2 +-
> > .../misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c | 163 ++++++++++++++++++
>
> Why doesn't this file live in the GPIO subsystem? Seems like this haven't
> got a proper review from the GPIO people (probably due to the "misc:"
> subject). Maybe even GPIO_REGMAP could be used.

I agree, plese resend this patch with the linux-gpio mailing list and the GPIO
maintainers on CC.

Yours,
Linus Walleij

2023-02-23 10:30:04

by Michael Walle

[permalink] [raw]
Subject: Re: [PATCH v1 char-misc-next 2/5] misc: microchip: pci1xxxx: load gpio driver for the gpio controller auxiliary device enumerated by the auxiliary bus driver.

Am 2023-02-23 11:23, schrieb Linus Walleij:
> On Fri, Feb 17, 2023 at 11:31 AM Michael Walle <[email protected]>
> wrote:
>> [+ GPIO maintainers]
>>
>> > PIO function's auxiliary bus driver enumerates separate child devices for
>> > GPIO controller and OTP/EEPROM interface. This gpio driver implemented
>> > based on the gpio framework is loaded for the gpio auxiliary device.
>> >
>> > Signed-off-by: Kumaravel Thiagarajan <[email protected]>
>> > ---
>> > MAINTAINERS | 1 +
>> > drivers/misc/mchp_pci1xxxx/Makefile | 2 +-
>> > .../misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c | 163 ++++++++++++++++++
>>
>> Why doesn't this file live in the GPIO subsystem? Seems like this
>> haven't
>> got a proper review from the GPIO people (probably due to the "misc:"
>> subject). Maybe even GPIO_REGMAP could be used.
>
> I agree, plese resend this patch with the linux-gpio mailing list and
> the GPIO
> maintainers on CC.

This is already in drivers/misc. There should be a follow up patch.

-michael