Add a function that allows initializing the valid_mask from
gpiochip_add_data.
This prevents race conditions during gpiochip initialization.
If the function is not exported, then the old behaviour is respected,
this is, set all gpios as valid.
Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/gpio/gpiolib.c | 16 ++++++++++++++--
include/linux/gpio/driver.h | 7 ++++++-
2 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e8f8a1999393..907019b67a58 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -359,7 +359,7 @@ static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
return p;
}
-static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
+static int gpiochip_alloc_valid_mask(struct gpio_chip *gpiochip)
{
#ifdef CONFIG_OF_GPIO
int size;
@@ -380,6 +380,14 @@ static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
return 0;
}
+static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
+{
+ if (gpiochip->init_valid_mask)
+ return gpiochip->init_valid_mask(gpiochip);
+
+ return 0;
+}
+
static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
{
kfree(gpiochip->valid_mask);
@@ -1367,7 +1375,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
if (status)
goto err_remove_from_list;
- status = gpiochip_init_valid_mask(chip);
+ status = gpiochip_alloc_valid_mask(chip);
if (status)
goto err_remove_irqchip_mask;
@@ -1379,6 +1387,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
if (status)
goto err_remove_chip;
+ status = gpiochip_init_valid_mask(chip);
+ if (status)
+ goto err_remove_chip;
+
acpi_gpiochip_add(chip);
machine_gpiochip_add(chip);
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 0ea328e71ec9..df09749269ff 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -256,6 +256,9 @@ struct gpio_chip {
void (*dbg_show)(struct seq_file *s,
struct gpio_chip *chip);
+
+ int (*init_valid_mask)(struct gpio_chip *chip);
+
int base;
u16 ngpio;
const char *const *names;
@@ -294,7 +297,9 @@ struct gpio_chip {
/**
* @need_valid_mask:
*
- * If set core allocates @valid_mask with all bits set to one.
+ * If set core allocates @valid_mask with all its values initialized
+ * with init_valid_mask() or set to one if init_valid_mask() is not
+ * defined
*/
bool need_valid_mask;
--
2.19.0
Current code assumes that the direction is input if direction_input
function is set.
This might not be the case on GPIOs with programmable direction.
Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/gpio/gpiolib.c | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 907019b67a58..e016b22658ff 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1349,20 +1349,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
spin_unlock_irqrestore(&gpio_lock, flags);
- for (i = 0; i < chip->ngpio; i++) {
- struct gpio_desc *desc = &gdev->descs[i];
-
- desc->gdev = gdev;
-
- /* REVISIT: most hardware initializes GPIOs as inputs (often
- * with pullups enabled) so power usage is minimized. Linux
- * code should set the gpio direction first thing; but until
- * it does, and in case chip->get_direction is not set, we may
- * expose the wrong direction in sysfs.
- */
- desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
- }
-
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&gdev->pin_ranges);
#endif
@@ -1391,6 +1377,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
if (status)
goto err_remove_chip;
+ for (i = 0; i < chip->ngpio; i++) {
+ struct gpio_desc *desc = &gdev->descs[i];
+
+ desc->gdev = gdev;
+
+ if (chip->get_direction && gpiochip_line_is_valid(chip, i))
+ desc->flags = !chip->get_direction(chip, i) ?
+ (1 << FLAG_IS_OUT) : 0;
+ else
+ desc->flags = !chip->direction_input ?
+ (1 << FLAG_IS_OUT) : 0;
+ }
+
acpi_gpiochip_add(chip);
machine_gpiochip_add(chip);
--
2.19.0
The current code produces XPU violation if get_direction is called just
after the initialization.
Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/pinctrl/qcom/pinctrl-msm.c | 79 ++++++++++++++----------------
1 file changed, 37 insertions(+), 42 deletions(-)
diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index 5d72ffad32c2..ce1ade47ea37 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -566,6 +566,42 @@ static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
#define msm_gpio_dbg_show NULL
#endif
+static int msm_gpio_init_valid_mask(struct gpio_chip *chip)
+{
+ struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
+ int ret;
+ unsigned int len, i;
+ unsigned int max_gpios = pctrl->soc->ngpios;
+ u16 *tmp;
+
+ /* The number of GPIOs in the ACPI tables */
+ len = ret = device_property_read_u16_array(pctrl->dev, "gpios", NULL,
+ 0);
+ if (ret < 0)
+ return 0;
+
+ if (ret > max_gpios)
+ return -EINVAL;
+
+ tmp = kmalloc_array(len, sizeof(*tmp), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ ret = device_property_read_u16_array(pctrl->dev, "gpios", tmp, len);
+ if (ret < 0) {
+ dev_err(pctrl->dev, "could not read list of GPIOs\n");
+ goto out;
+ }
+
+ bitmap_zero(chip->valid_mask, max_gpios);
+ for (i = 0; i < len; i++)
+ set_bit(tmp[i], chip->valid_mask);
+
+out:
+ kfree(tmp);
+ return ret;
+}
+
static const struct gpio_chip msm_gpio_template = {
.direction_input = msm_gpio_direction_input,
.direction_output = msm_gpio_direction_output,
@@ -575,6 +611,7 @@ static const struct gpio_chip msm_gpio_template = {
.request = gpiochip_generic_request,
.free = gpiochip_generic_free,
.dbg_show = msm_gpio_dbg_show,
+ .init_valid_mask = msm_gpio_init_valid_mask,
};
/* For dual-edge interrupts in software, since some hardware has no
@@ -855,41 +892,6 @@ static void msm_gpio_irq_handler(struct irq_desc *desc)
chained_irq_exit(chip, desc);
}
-static int msm_gpio_init_valid_mask(struct gpio_chip *chip,
- struct msm_pinctrl *pctrl)
-{
- int ret;
- unsigned int len, i;
- unsigned int max_gpios = pctrl->soc->ngpios;
- u16 *tmp;
-
- /* The number of GPIOs in the ACPI tables */
- len = ret = device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0);
- if (ret < 0)
- return 0;
-
- if (ret > max_gpios)
- return -EINVAL;
-
- tmp = kmalloc_array(len, sizeof(*tmp), GFP_KERNEL);
- if (!tmp)
- return -ENOMEM;
-
- ret = device_property_read_u16_array(pctrl->dev, "gpios", tmp, len);
- if (ret < 0) {
- dev_err(pctrl->dev, "could not read list of GPIOs\n");
- goto out;
- }
-
- bitmap_zero(chip->valid_mask, max_gpios);
- for (i = 0; i < len; i++)
- set_bit(tmp[i], chip->valid_mask);
-
-out:
- kfree(tmp);
- return ret;
-}
-
static bool msm_gpio_needs_valid_mask(struct msm_pinctrl *pctrl)
{
return device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0) > 0;
@@ -926,13 +928,6 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
return ret;
}
- ret = msm_gpio_init_valid_mask(chip, pctrl);
- if (ret) {
- dev_err(pctrl->dev, "Failed to setup irq valid bits\n");
- gpiochip_remove(&pctrl->chip);
- return ret;
- }
-
/*
* For DeviceTree-supported systems, the gpio core checks the
* pinctrl's device node for the "gpio-ranges" property.
--
2.19.0
On 10/5/2018 12:53 AM, Ricardo Ribalda Delgado wrote:
> Current code assumes that the direction is input if direction_input
> function is set.
> This might not be the case on GPIOs with programmable direction.
>
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> ---
> drivers/gpio/gpiolib.c | 27 +++++++++++++--------------
> 1 file changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 907019b67a58..e016b22658ff 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1349,20 +1349,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
>
> spin_unlock_irqrestore(&gpio_lock, flags);
>
> - for (i = 0; i < chip->ngpio; i++) {
> - struct gpio_desc *desc = &gdev->descs[i];
> -
> - desc->gdev = gdev;
> -
> - /* REVISIT: most hardware initializes GPIOs as inputs (often
> - * with pullups enabled) so power usage is minimized. Linux
> - * code should set the gpio direction first thing; but until
> - * it does, and in case chip->get_direction is not set, we may
> - * expose the wrong direction in sysfs.
> - */
> - desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
> - }
> -
> #ifdef CONFIG_PINCTRL
> INIT_LIST_HEAD(&gdev->pin_ranges);
> #endif
> @@ -1391,6 +1377,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
> if (status)
> goto err_remove_chip;
>
> + for (i = 0; i < chip->ngpio; i++) {
> + struct gpio_desc *desc = &gdev->descs[i];
> +
> + desc->gdev = gdev;
> +
> + if (chip->get_direction && gpiochip_line_is_valid(chip, i))
> + desc->flags = !chip->get_direction(chip, i) ?
> + (1 << FLAG_IS_OUT) : 0;
> + else
> + desc->flags = !chip->direction_input ?
> + (1 << FLAG_IS_OUT) : 0;
> + }
> +
> acpi_gpiochip_add(chip);
>
> machine_gpiochip_add(chip);
>
We have a successful boot this time.
Timur I see:
ubuntu@ubuntu:~$ dmesg | grep gpio
[ 7.388887] gpiochip_find_base: found new base at 362
[ 7.433186] gpio gpiochip0: (QCOM8002:00): added GPIO chardev (254:0)
[ 7.433218] gpiochip_setup_dev: registered GPIOs 362 to 511 on
device: gpiochip0 (QCOM8002:00)
[ 7.433222] gpio gpiochip0: (QCOM8002:00): created GPIO range 0->149
==> QCOM8002:00 PIN 0->149
Looks like the driver is initing just fine to me. Is setting up the
jumpers and running gpio-test warranted?
--
Jeffrey Hugo
Qualcomm Datacenter Technologies as an affiliate of Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.
On 10/05/2018 11:17 AM, Jeffrey Hugo wrote:>
> Looks like the driver is initing just fine to me. Is setting up the
> jumpers and running gpio-test warranted?
Well, that test only makes sure that input/output is actually working
on the hardware level, but it also makes sure that the GPIOs are
numbered correctly.
If you want, just put a printk(... offset) in msm_gpio_get() and read
from a GPIO that you know you have access to, and make sure the
'offset' is correct.
Then try reading from a GPIO that you don't have access to, and make
sure you get a failure before msm_gpio_get() is called.
On Fri, Oct 5, 2018 at 11:54 AM Timur Tabi <[email protected]> wrote:
> If you want, just put a printk(... offset) in msm_gpio_get() and read
> from a GPIO that you know you have access to, and make sure the
> 'offset' is correct.
>
> Then try reading from a GPIO that you don't have access to, and make
> sure you get a failure before msm_gpio_get() is called.
Just FYI, if you use sysfs to write to the GPIO, based on the kernel
log you pasted, GPIO 362 in sysfs is actually pin 0 in the TLMM.
If you use gpio-test, it uses gpiolib which figures this all out for
you. There should still be the gpio-test wiki page I wrote that tells
you how to use it.
On 10/5/18 1:52 AM, Ricardo Ribalda Delgado wrote:
> The current code produces XPU violation if get_direction is called just
> after the initialization.
>
> Signed-off-by: Ricardo Ribalda Delgado<[email protected]>
I'm not the maintainer of pinctrl-msm, but this looks okay to me.
Acked-by: Timur Tabi <[email protected]>
On 10/5/2018 10:54 AM, Timur Tabi wrote:
> On 10/05/2018 11:17 AM, Jeffrey Hugo wrote:>
>> Looks like the driver is initing just fine to me. Is setting up the
>> jumpers and running gpio-test warranted?
>
> Well, that test only makes sure that input/output is actually working
> on the hardware level, but it also makes sure that the GPIOs are
> numbered correctly.
>
> If you want, just put a printk(... offset) in msm_gpio_get() and read
> from a GPIO that you know you have access to, and make sure the
> 'offset' is correct.
>
> Then try reading from a GPIO that you don't have access to, and make
> sure you get a failure before msm_gpio_get() is called.
>
Done.
For the series:
Tested-by: Jeffrey Hugo <[email protected]>
--
Jeffrey Hugo
Qualcomm Datacenter Technologies as an affiliate of Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.
On Fri, Oct 5, 2018 at 8:53 AM Ricardo Ribalda Delgado
<[email protected]> wrote:
> Add a function that allows initializing the valid_mask from
> gpiochip_add_data.
>
> This prevents race conditions during gpiochip initialization.
>
> If the function is not exported, then the old behaviour is respected,
> this is, set all gpios as valid.
>
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
Patch applied,
thanks a lot for your hard work on this!
Yours,
Linus Walleij
On Fri, Oct 5, 2018 at 8:53 AM Ricardo Ribalda Delgado
<[email protected]> wrote:
> The current code produces XPU violation if get_direction is called just
> after the initialization.
>
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
Patch applied with Timur's ACK.
The code makes perfect sense.
I hope Bjorn has no reservations, if he does I guess I have to
just back it out.
Yours,
Linus Walleij
On Fri, Oct 5, 2018 at 8:53 AM Ricardo Ribalda Delgado
<[email protected]> wrote:
> Current code assumes that the direction is input if direction_input
> function is set.
> This might not be the case on GPIOs with programmable direction.
>
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
Patch applied with the collected ACKs.
Thanks for working so hard on fixing this up.
Yours,
Linus Walleij
Hi,
On Friday 05 October 2018 12:23 PM, Ricardo Ribalda Delgado wrote:
> Current code assumes that the direction is input if direction_input
> function is set.
> This might not be the case on GPIOs with programmable direction.
>
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> Tested-by: Jeffrey Hugo <[email protected]>
This patch causes oops on TI's AM335x-ICEv2 board on next-20181011:
[ 0.563797] OMAP GPIO hardware version 0.1
[ 0.577589] Unable to handle kernel NULL pointer dereference at virtual address 000002b8
[ 0.586127] pgd = (ptrval)
[ 0.588934] [000002b8] *pgd=00000000
[ 0.592732] Internal error: Oops: 5 [#1] SMP ARM
[ 0.597499] Modules linked in:
[ 0.600668] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7-next-20181011 #70
[ 0.608466] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 0.614770] PC is at gpiod_hog+0x30/0x154
[ 0.618913] LR is at of_gpiochip_add+0x2fc/0x4e4
[ 0.623671] pc : [<c055213c>] lr : [<c0553ff0>] psr: 60000013
[ 0.630130] sp : ce09bba0 ip : cdf08095 fp : 00000000
[ 0.635516] r10: c0bfcf24 r9 : 00000000 r8 : 00000007
[ 0.640902] r7 : cdf08088 r6 : 00000000 r5 : 00000000 r4 : ce191e40
[ 0.647630] r3 : 00000000 r2 : 00000000 r1 : cdf08088 r0 : ce191e40
[ 0.654361] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
[ 0.661718] Control: 10c5387d Table: 80004019 DAC: 00000051
[ 0.667642] Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
[...]
[ 0.973593] [<c055213c>] (gpiod_hog) from [<c0553ff0>] (of_gpiochip_add+0x2fc/0x4e4)
[ 0.981588] [<c0553ff0>] (of_gpiochip_add) from [<c05528a0>] (gpiochip_add_data_with_key+
0x5a0/0x990)
[ 0.991102] [<c05528a0>] (gpiochip_add_data_with_key) from [<c0556d8c>] (omap_gpio_probe+
0x37c/0x75c)
[ 1.000613] [<c0556d8c>] (omap_gpio_probe) from [<c06049c0>] (platform_drv_probe+0x48/0x9
8)
[ 1.009237] [<c06049c0>] (platform_drv_probe) from [<c0602a04>] (really_probe+0x220/0x2d4
)
[ 1.017764] [<c0602a04>] (really_probe) from [<c0602c18>] (driver_probe_device+0x5c/0x164
)
[ 1.026293] [<c0602c18>] (driver_probe_device) from [<c0600d44>] (bus_for_each_drv+0x54/0
xb8)
[ 1.035090] [<c0600d44>] (bus_for_each_drv) from [<c060276c>] (__device_attach+0xcc/0x13c
)
[ 1.043615] [<c060276c>] (__device_attach) from [<c0601b88>] (bus_probe_device+0x88/0x90)
[ 1.052051] [<c0601b88>] (bus_probe_device) from [<c05fea18>] (device_add+0x3d8/0x608)
[ 1.060223] [<c05fea18>] (device_add) from [<c07343b8>] (of_platform_device_create_pdata+
0x8c/0xc0)
[ 1.069552] [<c07343b8>] (of_platform_device_create_pdata) from [<c07345c4>] (of_platform
_bus_create+0x190/0x228)
[ 1.080134] [<c07345c4>] (of_platform_bus_create) from [<c0734610>] (of_platform_bus_crea
te+0x1dc/0x228)
[ 1.089909] [<c0734610>] (of_platform_bus_create) from [<c073478c>] (of_platform_populate
+0x5c/0xac)
[ 1.099333] [<c073478c>] (of_platform_populate) from [<c0d12614>] (pdata_quirks_init+0x6c
/0x90)
[ 1.108306] [<c0d12614>] (pdata_quirks_init) from [<c0d12144>] (omap_generic_init+0xc/0x1
8)
[ 1.116933] [<c0d12144>] (omap_generic_init) from [<c0d03eb0>] (customize_machine+0x1c/0x
30)
[ 1.125645] [<c0d03eb0>] (customize_machine) from [<c01030e4>] (do_one_initcall+0x80/0x31
0)
[ 1.134265] [<c01030e4>] (do_one_initcall) from [<c0d01244>] (kernel_init_freeable+0x3c4/
0x4ac)
[ 1.143238] [<c0d01244>] (kernel_init_freeable) from [<c0900f28>] (kernel_init+0x8/0x114)
[ 1.151673] [<c0900f28>] (kernel_init) from [<c01010b4>] (ret_from_fork+0x14/0x20)
[ 1.159475] Exception stack(0xce09bfb0 to 0xce09bff8)
[ 1.164686] bfa0: 00000000 00000000 00000000 00000000
[ 1.173119] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[ 1.181551] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 1.188378] Code: 0a000002 e3530000 01a09003 159392b4 (e59352b8)
[ 1.194766] ---[ end trace d5c17cd400f50a22 ]---
[ 1.199606] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[ 1.199606]
[ 1.209052] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000
00b
[ 1.209052] ]---
[ 3.172292] random: fast init done
Full log: https://pastebin.ubuntu.com/p/jG8nN6CTBP/
Reverting this patch from linux-next allows to boot to prompt.
Regards
Vignesh
> ---
> drivers/gpio/gpiolib.c | 27 +++++++++++++--------------
> 1 file changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 907019b67a58..e016b22658ff 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1349,20 +1349,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
>
> spin_unlock_irqrestore(&gpio_lock, flags);
>
> - for (i = 0; i < chip->ngpio; i++) {
> - struct gpio_desc *desc = &gdev->descs[i];
> -
> - desc->gdev = gdev;
> -
> - /* REVISIT: most hardware initializes GPIOs as inputs (often
> - * with pullups enabled) so power usage is minimized. Linux
> - * code should set the gpio direction first thing; but until
> - * it does, and in case chip->get_direction is not set, we may
> - * expose the wrong direction in sysfs.
> - */
> - desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
> - }
> -
> #ifdef CONFIG_PINCTRL
> INIT_LIST_HEAD(&gdev->pin_ranges);
> #endif
> @@ -1391,6 +1377,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
> if (status)
> goto err_remove_chip;
>
> + for (i = 0; i < chip->ngpio; i++) {
> + struct gpio_desc *desc = &gdev->descs[i];
> +
> + desc->gdev = gdev;
> +
> + if (chip->get_direction && gpiochip_line_is_valid(chip, i))
> + desc->flags = !chip->get_direction(chip, i) ?
> + (1 << FLAG_IS_OUT) : 0;
> + else
> + desc->flags = !chip->direction_input ?
> + (1 << FLAG_IS_OUT) : 0;
> + }
> +
> acpi_gpiochip_add(chip);
>
> machine_gpiochip_add(chip);
>
Hi Vignesh
Ups, it does not look too good :S . Can you check if this change fixes it:
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e016b22658ff..bcd0ef49ce97 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1349,6 +1349,9 @@ int gpiochip_add_data_with_key(struct gpio_chip
*chip, void *data,
spin_unlock_irqrestore(&gpio_lock, flags);
+ for (i = 0; i < chip->ngpio; i++)
+ gdev->descs[i].gdev = gdev;
+
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&gdev->pin_ranges);
#endif
@@ -1380,8 +1383,6 @@ int gpiochip_add_data_with_key(struct gpio_chip
*chip, void *data,
for (i = 0; i < chip->ngpio; i++) {
struct gpio_desc *desc = &gdev->descs[i];
- desc->gdev = gdev;
-
if (chip->get_direction && gpiochip_line_is_valid(chip, i))
desc->flags = !chip->get_direction(chip, i) ?
(1 << FLAG_IS_OUT) : 0;
Thanks!
On Thu, Oct 11, 2018 at 2:18 PM Vignesh R <[email protected]> wrote:
>
> Hi,
>
> On Friday 05 October 2018 12:23 PM, Ricardo Ribalda Delgado wrote:
> > Current code assumes that the direction is input if direction_input
> > function is set.
> > This might not be the case on GPIOs with programmable direction.
> >
> > Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> > Tested-by: Jeffrey Hugo <[email protected]>
>
> This patch causes oops on TI's AM335x-ICEv2 board on next-20181011:
>
> [ 0.563797] OMAP GPIO hardware version 0.1
> [ 0.577589] Unable to handle kernel NULL pointer dereference at virtual address 000002b8
> [ 0.586127] pgd = (ptrval)
> [ 0.588934] [000002b8] *pgd=00000000
> [ 0.592732] Internal error: Oops: 5 [#1] SMP ARM
> [ 0.597499] Modules linked in:
> [ 0.600668] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7-next-20181011 #70
> [ 0.608466] Hardware name: Generic AM33XX (Flattened Device Tree)
> [ 0.614770] PC is at gpiod_hog+0x30/0x154
> [ 0.618913] LR is at of_gpiochip_add+0x2fc/0x4e4
> [ 0.623671] pc : [<c055213c>] lr : [<c0553ff0>] psr: 60000013
> [ 0.630130] sp : ce09bba0 ip : cdf08095 fp : 00000000
> [ 0.635516] r10: c0bfcf24 r9 : 00000000 r8 : 00000007
> [ 0.640902] r7 : cdf08088 r6 : 00000000 r5 : 00000000 r4 : ce191e40
> [ 0.647630] r3 : 00000000 r2 : 00000000 r1 : cdf08088 r0 : ce191e40
> [ 0.654361] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
> [ 0.661718] Control: 10c5387d Table: 80004019 DAC: 00000051
> [ 0.667642] Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
> [...]
> [ 0.973593] [<c055213c>] (gpiod_hog) from [<c0553ff0>] (of_gpiochip_add+0x2fc/0x4e4)
> [ 0.981588] [<c0553ff0>] (of_gpiochip_add) from [<c05528a0>] (gpiochip_add_data_with_key+
> 0x5a0/0x990)
> [ 0.991102] [<c05528a0>] (gpiochip_add_data_with_key) from [<c0556d8c>] (omap_gpio_probe+
> 0x37c/0x75c)
> [ 1.000613] [<c0556d8c>] (omap_gpio_probe) from [<c06049c0>] (platform_drv_probe+0x48/0x9
> 8)
> [ 1.009237] [<c06049c0>] (platform_drv_probe) from [<c0602a04>] (really_probe+0x220/0x2d4
> )
> [ 1.017764] [<c0602a04>] (really_probe) from [<c0602c18>] (driver_probe_device+0x5c/0x164
> )
> [ 1.026293] [<c0602c18>] (driver_probe_device) from [<c0600d44>] (bus_for_each_drv+0x54/0
> xb8)
> [ 1.035090] [<c0600d44>] (bus_for_each_drv) from [<c060276c>] (__device_attach+0xcc/0x13c
> )
> [ 1.043615] [<c060276c>] (__device_attach) from [<c0601b88>] (bus_probe_device+0x88/0x90)
> [ 1.052051] [<c0601b88>] (bus_probe_device) from [<c05fea18>] (device_add+0x3d8/0x608)
> [ 1.060223] [<c05fea18>] (device_add) from [<c07343b8>] (of_platform_device_create_pdata+
> 0x8c/0xc0)
> [ 1.069552] [<c07343b8>] (of_platform_device_create_pdata) from [<c07345c4>] (of_platform
> _bus_create+0x190/0x228)
> [ 1.080134] [<c07345c4>] (of_platform_bus_create) from [<c0734610>] (of_platform_bus_crea
> te+0x1dc/0x228)
> [ 1.089909] [<c0734610>] (of_platform_bus_create) from [<c073478c>] (of_platform_populate
> +0x5c/0xac)
> [ 1.099333] [<c073478c>] (of_platform_populate) from [<c0d12614>] (pdata_quirks_init+0x6c
> /0x90)
> [ 1.108306] [<c0d12614>] (pdata_quirks_init) from [<c0d12144>] (omap_generic_init+0xc/0x1
> 8)
> [ 1.116933] [<c0d12144>] (omap_generic_init) from [<c0d03eb0>] (customize_machine+0x1c/0x
> 30)
> [ 1.125645] [<c0d03eb0>] (customize_machine) from [<c01030e4>] (do_one_initcall+0x80/0x31
> 0)
> [ 1.134265] [<c01030e4>] (do_one_initcall) from [<c0d01244>] (kernel_init_freeable+0x3c4/
> 0x4ac)
> [ 1.143238] [<c0d01244>] (kernel_init_freeable) from [<c0900f28>] (kernel_init+0x8/0x114)
> [ 1.151673] [<c0900f28>] (kernel_init) from [<c01010b4>] (ret_from_fork+0x14/0x20)
> [ 1.159475] Exception stack(0xce09bfb0 to 0xce09bff8)
> [ 1.164686] bfa0: 00000000 00000000 00000000 00000000
> [ 1.173119] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> [ 1.181551] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
> [ 1.188378] Code: 0a000002 e3530000 01a09003 159392b4 (e59352b8)
> [ 1.194766] ---[ end trace d5c17cd400f50a22 ]---
> [ 1.199606] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
> [ 1.199606]
> [ 1.209052] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000
> 00b
> [ 1.209052] ]---
> [ 3.172292] random: fast init done
>
> Full log: https://pastebin.ubuntu.com/p/jG8nN6CTBP/
>
> Reverting this patch from linux-next allows to boot to prompt.
>
> Regards
> Vignesh
>
> > ---
> > drivers/gpio/gpiolib.c | 27 +++++++++++++--------------
> > 1 file changed, 13 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> > index 907019b67a58..e016b22658ff 100644
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -1349,20 +1349,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
> >
> > spin_unlock_irqrestore(&gpio_lock, flags);
> >
> > - for (i = 0; i < chip->ngpio; i++) {
> > - struct gpio_desc *desc = &gdev->descs[i];
> > -
> > - desc->gdev = gdev;
> > -
> > - /* REVISIT: most hardware initializes GPIOs as inputs (often
> > - * with pullups enabled) so power usage is minimized. Linux
> > - * code should set the gpio direction first thing; but until
> > - * it does, and in case chip->get_direction is not set, we may
> > - * expose the wrong direction in sysfs.
> > - */
> > - desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
> > - }
> > -
> > #ifdef CONFIG_PINCTRL
> > INIT_LIST_HEAD(&gdev->pin_ranges);
> > #endif
> > @@ -1391,6 +1377,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
> > if (status)
> > goto err_remove_chip;
> >
> > + for (i = 0; i < chip->ngpio; i++) {
> > + struct gpio_desc *desc = &gdev->descs[i];
> > +
> > + desc->gdev = gdev;
> > +
> > + if (chip->get_direction && gpiochip_line_is_valid(chip, i))
> > + desc->flags = !chip->get_direction(chip, i) ?
> > + (1 << FLAG_IS_OUT) : 0;
> > + else
> > + desc->flags = !chip->direction_input ?
> > + (1 << FLAG_IS_OUT) : 0;
> > + }
> > +
> > acpi_gpiochip_add(chip);
> >
> > machine_gpiochip_add(chip);
> >
>
--
Ricardo Ribalda
Hi,
On Thursday 11 October 2018 07:12 PM, Ricardo Ribalda Delgado wrote:
> Hi Vignesh
>
> Ups, it does not look too good :S . Can you check if this change fixes it:
>
Below diff works for me. I no longer see crash and gpio-hog seems to be
working. Thanks!
Regards
Vignesh
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index e016b22658ff..bcd0ef49ce97 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1349,6 +1349,9 @@ int gpiochip_add_data_with_key(struct gpio_chip
> *chip, void *data,
>
> spin_unlock_irqrestore(&gpio_lock, flags);
>
> + for (i = 0; i < chip->ngpio; i++)
> + gdev->descs[i].gdev = gdev;
> +
> #ifdef CONFIG_PINCTRL
> INIT_LIST_HEAD(&gdev->pin_ranges);
> #endif
> @@ -1380,8 +1383,6 @@ int gpiochip_add_data_with_key(struct gpio_chip
> *chip, void *data,
> for (i = 0; i < chip->ngpio; i++) {
> struct gpio_desc *desc = &gdev->descs[i];
>
> - desc->gdev = gdev;
> -
> if (chip->get_direction && gpiochip_line_is_valid(chip, i))
> desc->flags = !chip->get_direction(chip, i) ?
> (1 << FLAG_IS_OUT) : 0;
>
>
> Thanks!
> On Thu, Oct 11, 2018 at 2:18 PM Vignesh R <[email protected]> wrote:
>>
>> Hi,
>>
>> On Friday 05 October 2018 12:23 PM, Ricardo Ribalda Delgado wrote:
>>> Current code assumes that the direction is input if direction_input
>>> function is set.
>>> This might not be the case on GPIOs with programmable direction.
>>>
>>> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
>>> Tested-by: Jeffrey Hugo <[email protected]>
>>
>> This patch causes oops on TI's AM335x-ICEv2 board on next-20181011:
>>
>> [ 0.563797] OMAP GPIO hardware version 0.1
>> [ 0.577589] Unable to handle kernel NULL pointer dereference at virtual address 000002b8
>> [ 0.586127] pgd = (ptrval)
>> [ 0.588934] [000002b8] *pgd=00000000
>> [ 0.592732] Internal error: Oops: 5 [#1] SMP ARM
>> [ 0.597499] Modules linked in:
>> [ 0.600668] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7-next-20181011 #70
>> [ 0.608466] Hardware name: Generic AM33XX (Flattened Device Tree)
>> [ 0.614770] PC is at gpiod_hog+0x30/0x154
>> [ 0.618913] LR is at of_gpiochip_add+0x2fc/0x4e4
>> [ 0.623671] pc : [<c055213c>] lr : [<c0553ff0>] psr: 60000013
>> [ 0.630130] sp : ce09bba0 ip : cdf08095 fp : 00000000
>> [ 0.635516] r10: c0bfcf24 r9 : 00000000 r8 : 00000007
>> [ 0.640902] r7 : cdf08088 r6 : 00000000 r5 : 00000000 r4 : ce191e40
>> [ 0.647630] r3 : 00000000 r2 : 00000000 r1 : cdf08088 r0 : ce191e40
>> [ 0.654361] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
>> [ 0.661718] Control: 10c5387d Table: 80004019 DAC: 00000051
>> [ 0.667642] Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
>> [...]
>> [ 0.973593] [<c055213c>] (gpiod_hog) from [<c0553ff0>] (of_gpiochip_add+0x2fc/0x4e4)
>> [ 0.981588] [<c0553ff0>] (of_gpiochip_add) from [<c05528a0>] (gpiochip_add_data_with_key+
>> 0x5a0/0x990)
>> [ 0.991102] [<c05528a0>] (gpiochip_add_data_with_key) from [<c0556d8c>] (omap_gpio_probe+
>> 0x37c/0x75c)
>> [ 1.000613] [<c0556d8c>] (omap_gpio_probe) from [<c06049c0>] (platform_drv_probe+0x48/0x9
>> 8)
>> [ 1.009237] [<c06049c0>] (platform_drv_probe) from [<c0602a04>] (really_probe+0x220/0x2d4
>> )
>> [ 1.017764] [<c0602a04>] (really_probe) from [<c0602c18>] (driver_probe_device+0x5c/0x164
>> )
>> [ 1.026293] [<c0602c18>] (driver_probe_device) from [<c0600d44>] (bus_for_each_drv+0x54/0
>> xb8)
>> [ 1.035090] [<c0600d44>] (bus_for_each_drv) from [<c060276c>] (__device_attach+0xcc/0x13c
>> )
>> [ 1.043615] [<c060276c>] (__device_attach) from [<c0601b88>] (bus_probe_device+0x88/0x90)
>> [ 1.052051] [<c0601b88>] (bus_probe_device) from [<c05fea18>] (device_add+0x3d8/0x608)
>> [ 1.060223] [<c05fea18>] (device_add) from [<c07343b8>] (of_platform_device_create_pdata+
>> 0x8c/0xc0)
>> [ 1.069552] [<c07343b8>] (of_platform_device_create_pdata) from [<c07345c4>] (of_platform
>> _bus_create+0x190/0x228)
>> [ 1.080134] [<c07345c4>] (of_platform_bus_create) from [<c0734610>] (of_platform_bus_crea
>> te+0x1dc/0x228)
>> [ 1.089909] [<c0734610>] (of_platform_bus_create) from [<c073478c>] (of_platform_populate
>> +0x5c/0xac)
>> [ 1.099333] [<c073478c>] (of_platform_populate) from [<c0d12614>] (pdata_quirks_init+0x6c
>> /0x90)
>> [ 1.108306] [<c0d12614>] (pdata_quirks_init) from [<c0d12144>] (omap_generic_init+0xc/0x1
>> 8)
>> [ 1.116933] [<c0d12144>] (omap_generic_init) from [<c0d03eb0>] (customize_machine+0x1c/0x
>> 30)
>> [ 1.125645] [<c0d03eb0>] (customize_machine) from [<c01030e4>] (do_one_initcall+0x80/0x31
>> 0)
>> [ 1.134265] [<c01030e4>] (do_one_initcall) from [<c0d01244>] (kernel_init_freeable+0x3c4/
>> 0x4ac)
>> [ 1.143238] [<c0d01244>] (kernel_init_freeable) from [<c0900f28>] (kernel_init+0x8/0x114)
>> [ 1.151673] [<c0900f28>] (kernel_init) from [<c01010b4>] (ret_from_fork+0x14/0x20)
>> [ 1.159475] Exception stack(0xce09bfb0 to 0xce09bff8)
>> [ 1.164686] bfa0: 00000000 00000000 00000000 00000000
>> [ 1.173119] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>> [ 1.181551] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000
>> [ 1.188378] Code: 0a000002 e3530000 01a09003 159392b4 (e59352b8)
>> [ 1.194766] ---[ end trace d5c17cd400f50a22 ]---
>> [ 1.199606] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
>> [ 1.199606]
>> [ 1.209052] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000
>> 00b
>> [ 1.209052] ]---
>> [ 3.172292] random: fast init done
>>
>> Full log: https://pastebin.ubuntu.com/p/jG8nN6CTBP/
>>
>> Reverting this patch from linux-next allows to boot to prompt.
>>
>> Regards
>> Vignesh
>>
>>> ---
>>> drivers/gpio/gpiolib.c | 27 +++++++++++++--------------
>>> 1 file changed, 13 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
>>> index 907019b67a58..e016b22658ff 100644
>>> --- a/drivers/gpio/gpiolib.c
>>> +++ b/drivers/gpio/gpiolib.c
>>> @@ -1349,20 +1349,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
>>>
>>> spin_unlock_irqrestore(&gpio_lock, flags);
>>>
>>> - for (i = 0; i < chip->ngpio; i++) {
>>> - struct gpio_desc *desc = &gdev->descs[i];
>>> -
>>> - desc->gdev = gdev;
>>> -
>>> - /* REVISIT: most hardware initializes GPIOs as inputs (often
>>> - * with pullups enabled) so power usage is minimized. Linux
>>> - * code should set the gpio direction first thing; but until
>>> - * it does, and in case chip->get_direction is not set, we may
>>> - * expose the wrong direction in sysfs.
>>> - */
>>> - desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;
>>> - }
>>> -
>>> #ifdef CONFIG_PINCTRL
>>> INIT_LIST_HEAD(&gdev->pin_ranges);
>>> #endif
>>> @@ -1391,6 +1377,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
>>> if (status)
>>> goto err_remove_chip;
>>>
>>> + for (i = 0; i < chip->ngpio; i++) {
>>> + struct gpio_desc *desc = &gdev->descs[i];
>>> +
>>> + desc->gdev = gdev;
>>> +
>>> + if (chip->get_direction && gpiochip_line_is_valid(chip, i))
>>> + desc->flags = !chip->get_direction(chip, i) ?
>>> + (1 << FLAG_IS_OUT) : 0;
>>> + else
>>> + desc->flags = !chip->direction_input ?
>>> + (1 << FLAG_IS_OUT) : 0;
>>> + }
>>> +
>>> acpi_gpiochip_add(chip);
>>>
>>> machine_gpiochip_add(chip);
>>>
>>
>
>
On Fri, Oct 12, 2018 at 7:59 AM Vignesh R <[email protected]> wrote:
> On Thursday 11 October 2018 07:12 PM, Ricardo Ribalda Delgado wrote:
> > Hi Vignesh
> >
> > Ups, it does not look too good :S . Can you check if this change fixes it:
> >
>
> Below diff works for me. I no longer see crash and gpio-hog seems to be
> working. Thanks!
Ricardo can you send a patch with a Fixes: tag and Vignesh's
Tested-by/Reported-by?
Yours,
Linus Walleij
On Fri, 2018-10-05 at 08:53 +0200, Ricardo Ribalda Delgado wrote:
> Current code assumes that the direction is input if direction_input
> function is set.
> This might not be the case on GPIOs with programmable direction.
Unfortunately, this breaks at least Apalis T30 and Apalis TK1. Enabling
earlycon reveals the following:
[ 0.721165] Unable to handle kernel NULL pointer dereference at
virtual addre
ss 000001f8
[ 0.729570] pgd = (ptrval)
[ 0.732417] [000001f8] *pgd=00000000
[ 0.736137] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
[ 0.741643] Modules linked in:
[ 0.744819] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7-
next-2018101
2 #6
[ 0.752579] Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
[ 0.759092] PC is at gpiod_hog+0x2c/0x150
[ 0.763255] LR is at of_gpiochip_add+0x34c/0x510
[ 0.768040] pc : [<c044c9a4>] lr : [<c044e840>] psr: 60000013
[ 0.774534] sp : f68c9cd0 ip : 00000000 fp : f68c9d18
[ 0.779946] r10: c0ccb3c8 r9 : 00000000 r8 : 00000000
[ 0.785359] r7 : 00000007 r6 : c20019c4 r5 : f6a7b970 r4 :
f6a78a24
[ 0.792121] r3 : 00000000 r2 : 00000000 r1 : c20019c4 r0 :
f6a7b970
[ 0.798884] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA
ARM Segment none
[ 0.806273] Control: 10c5387d Table: 8000404a DAC: 00000051
[ 0.812227] Process swapper/0 (pid: 1, stack limit = 0x(ptrval))
[ 0.818451] Stack: (0xf68c9cd0 to 0xf68ca000)
...
[ 1.043490] [<c044c9a4>] (gpiod_hog) from [<c044e840>]
(of_gpiochip_add+0x34c/0x510)
[ 1.051531] [<c044e840>] (of_gpiochip_add) from [<c044d1cc>]
(gpiochip_add_data_with_key+0x668/0x958)
[ 1.061091] [<c044d1cc>] (gpiochip_add_data_with_key) from
[<c044d504>] (devm_gpiochip_add_data+0x48/0x84)
[ 1.071109] [<c044d504>] (devm_gpiochip_add_data) from [<c045166c>]
(tegra_gpio_probe+0x2d4/0x420)
[ 1.080413] [<c045166c>] (tegra_gpio_probe) from [<c0574040>]
(platform_drv_probe+0x48/0x98)
[ 1.089171] [<c0574040>] (platform_drv_probe) from [<c0572164>]
(really_probe+0x1e0/0x2cc)
[ 1.097746] [<c0572164>] (really_probe) from [<c05723b4>]
(driver_probe_device+0x60/0x16c)
[ 1.106317] [<c05723b4>] (driver_probe_device) from [<c057259c>]
(__driver_attach+0xdc/0xe0)
[ 1.115071] [<c057259c>] (__driver_attach) from [<c05704a8>]
(bus_for_each_dev+0x74/0xb4)
[ 1.123554] [<c05704a8>] (bus_for_each_dev) from [<c0571644>]
(bus_add_driver+0x1c0/0x204)
[ 1.132122] [<c0571644>] (bus_add_driver) from [<c05731b8>]
(driver_register+0x74/0x108)
[ 1.140521] [<c05731b8>] (driver_register) from [<c0102ebc>]
(do_one_initcall+0x54/0x284)
[ 1.149015] [<c0102ebc>] (do_one_initcall) from [<c0e01134>]
(kernel_init_freeable+0x2d0/0x364)
[ 1.158043] [<c0e01134>] (kernel_init_freeable) from [<c0a24c78>]
(kernel_init+0x8/0x110)
[ 1.166527] [<c0a24c78>] (kernel_init) from [<c01010e8>]
(ret_from_fork+0x14/0x2c)
[ 1.174375] Exception stack(0xf68c9fb0 to 0xf68c9ff8)
...
Just reverting this one patch made it boot again. I will investigate
further...
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> ---
> drivers/gpio/gpiolib.c | 27 +++++++++++++--------------
> 1 file changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 907019b67a58..e016b22658ff 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1349,20 +1349,6 @@ int gpiochip_add_data_with_key(struct
> gpio_chip *chip, void *data,
>
> spin_unlock_irqrestore(&gpio_lock, flags);
>
> - for (i = 0; i < chip->ngpio; i++) {
> - struct gpio_desc *desc = &gdev->descs[i];
> -
> - desc->gdev = gdev;
> -
> - /* REVISIT: most hardware initializes GPIOs as
> inputs (often
> - * with pullups enabled) so power usage is
> minimized. Linux
> - * code should set the gpio direction first thing;
> but until
> - * it does, and in case chip->get_direction is not
> set, we may
> - * expose the wrong direction in sysfs.
> - */
> - desc->flags = !chip->direction_input ? (1 <<
> FLAG_IS_OUT) : 0;
> - }
> -
> #ifdef CONFIG_PINCTRL
> INIT_LIST_HEAD(&gdev->pin_ranges);
> #endif
> @@ -1391,6 +1377,19 @@ int gpiochip_add_data_with_key(struct
> gpio_chip *chip, void *data,
> if (status)
> goto err_remove_chip;
>
> + for (i = 0; i < chip->ngpio; i++) {
> + struct gpio_desc *desc = &gdev->descs[i];
> +
> + desc->gdev = gdev;
> +
> + if (chip->get_direction &&
> gpiochip_line_is_valid(chip, i))
> + desc->flags = !chip->get_direction(chip, i)
> ?
> + (1 << FLAG_IS_OUT) : 0;
> + else
> + desc->flags = !chip->direction_input ?
> + (1 << FLAG_IS_OUT) : 0;
> + }
> +
> acpi_gpiochip_add(chip);
>
> machine_gpiochip_add(chip);
On Fri, Oct 12, 2018 at 11:00 AM Marcel Ziswiler
<[email protected]> wrote:
> On Fri, 2018-10-05 at 08:53 +0200, Ricardo Ribalda Delgado wrote:
> > Current code assumes that the direction is input if direction_input
> > function is set.
> > This might not be the case on GPIOs with programmable direction.
>
> Unfortunately, this breaks at least Apalis T30 and Apalis TK1. Enabling
> earlycon reveals the following:
Does this (just applied) patch fix the issue?
https://marc.info/?l=linux-kernel&m=153932470412013&w=2
Yours,
Linus Walleij
On Fri, 2018-10-12 at 11:08 +0200, Linus Walleij wrote:
> On Fri, Oct 12, 2018 at 11:00 AM Marcel Ziswiler
> <[email protected]> wrote:
> > On Fri, 2018-10-05 at 08:53 +0200, Ricardo Ribalda Delgado wrote:
> > > Current code assumes that the direction is input if
> > > direction_input
> > > function is set.
> > > This might not be the case on GPIOs with programmable direction.
> >
> > Unfortunately, this breaks at least Apalis T30 and Apalis TK1.
> > Enabling
> > earlycon reveals the following:
>
> Does this (just applied) patch fix the issue?
> https://marc.info/?l=linux-kernel&m=153932470412013&w=2
Yes, that cuts it. Thanks!
> Yours,
> Linus Walleij