[PATCH v3 2/2] Input: ads7846: use gpio_request_one to configure pendown_gpio
G, Manjunath Kondaiah
manjugk at ti.com
Fri Feb 4 08:32:50 EST 2011
On Thu, Feb 03, 2011 at 09:19:53AM -0800, Dmitry Torokhov wrote:
> On Thu, Feb 03, 2011 at 08:54:05AM -0800, Dmitry Torokhov wrote:
> > On Thu, Feb 03, 2011 at 08:51:46PM +0530, Sourav Poddar wrote:
> > > The ads7846 driver requests a gpio but does not currently
> > > configure it explicitly as an input. Use gpio_request_one
> > > to request and configure it at one shot.
> > >
> > > Signed-off-by: Sourav Poddar <sourav.poddar at ti.com>
> > > Cc: Dmitry Torokhov <dtor at mail.ru>
> >
> > Will apply this one, the other one is a bit messy IMO, will have to
> > think about it.
> >
>
> Something like below should do I think.
Patch looks good but it applies only on top of previous patch:
https://patchwork.kernel.org/patch/529941/
Why to have two patches for this fix?
Both the patches can be merged as:
diff --git a/drivers/input/touchscreen/ads7846.c
b/drivers/input/touchscreen/ads7846.c
index 14ea54b..940967b 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -941,29 +941,30 @@ static int __devinit ads7846_setup_pendown(struct
spi_device *spi, struct ads784
struct ads7846_platform_data *pdata = spi->dev.platform_data;
int err;
- /* REVISIT when the irq can be triggered active-low, or if for
some
+ /*
+ * REVISIT when the irq can be triggered active-low, or if for
some
* reason the touchscreen isn't hooked up, we don't need to
* access
* the pendown state.
*/
- if (!pdata->get_pendown_state &&
!gpio_is_valid(pdata->gpio_pendown)) {
- dev_err(&spi->dev, "no get_pendown_state nor
gpio_pendown?\n");
- return -EINVAL;
- }
if (pdata->get_pendown_state) {
ts->get_pendown_state = pdata->get_pendown_state;
- return 0;
- }
+ } else if (gpio_is_valid(pdata->gpio_pendown)) {
+
+ err = gpio_request_one(pdata->gpio_pendown,
GPIOF_DIR_IN,
+
"ads7846_pendown");
+ if (err) {
+ dev_err(&spi->dev, "failed to request pendown
GPIO%d\n",
+ pdata->gpio_pendown);
+ return err;
+ }
- err = gpio_request(pdata->gpio_pendown, "ads7846_pendown");
- if (err) {
- dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
- pdata->gpio_pendown);
- return err;
+ ts->gpio_pendown = pdata->gpio_pendown;
+ } else {
+ dev_err(&spi->dev, "no get_pendown_state nor
gpio_pendown?\n");
+ return -EINVAL;
}
- ts->gpio_pendown = pdata->gpio_pendown;
-
return 0;
}
@@ -1353,7 +1354,7 @@ static int __devinit ads7846_probe(struct
spi_device *spi)
err_put_regulator:
regulator_put(ts->reg);
err_free_gpio:
- if (ts->gpio_pendown != -1)
+ if (!ts->get_pendown_state)
gpio_free(ts->gpio_pendown);
err_cleanup_filter:
if (ts->filter_cleanup)
@@ -1383,8 +1384,13 @@ static int __devexit ads7846_remove(struct
spi_device *spi)
regulator_disable(ts->reg);
regulator_put(ts->reg);
- if (ts->gpio_pendown != -1)
+ if (!ts->get_pendown_state) {
+ /*
+ * If we are not using specialized pendown method we
must
+ * have been relying on gpio we set up ourselves.
+ */
gpio_free(ts->gpio_pendown);
+ }
if (ts->filter_cleanup)
ts->filter_cleanup(ts->filter_data);
>
> --
> Dmitry
>
>
> Input: ads7846 - check proper condition when freeing gpio
>
> From: Dmitry Torokhov <dmitry.torokhov at gmail.com>
>
> When driver uses custom pendown detection method gpio_pendown is not
> set up and so we should not try to free it, otherwise we are presented
> with:
>
> ------------[ cut here ]------------
> WARNING: at drivers/gpio/gpiolib.c:1258 gpio_free+0x100/0x12c()
> Modules linked in:
> [<c0061208>] (unwind_backtrace+0x0/0xe4) from [<c0091f58>](warn_slowpath_common+0x4c/0x64)
> [<c0091f58>] (warn_slowpath_common+0x4c/0x64) from [<c0091f88>](warn_slowpath_null+0x18/0x1c)
> [<c0091f88>] (warn_slowpath_null+0x18/0x1c) from [<c024e610>](gpio_free+0x100/0x12c)
> [<c024e610>] (gpio_free+0x100/0x12c) from [<c03e9fbc>](ads7846_probe+0xa38/0xc5c)
> [<c03e9fbc>] (ads7846_probe+0xa38/0xc5c) from [<c02cff14>](spi_drv_probe+0x18/0x1c)
> [<c02cff14>] (spi_drv_probe+0x18/0x1c) from [<c028bca4>](driver_probe_device+0xc8/0x184)
> [<c028bca4>] (driver_probe_device+0xc8/0x184) from [<c028bdc8>](__driver_attach+0x68/0x8c)
> [<c028bdc8>] (__driver_attach+0x68/0x8c) from [<c028b4c8>](bus_for_each_dev+0x48/0x74)
> [<c028b4c8>] (bus_for_each_dev+0x48/0x74) from [<c028ae08>](bus_add_driver+0xa0/0x220)
> [<c028ae08>] (bus_add_driver+0xa0/0x220) from [<c028c0c0>](driver_register+0xa8/0x134)
> [<c028c0c0>] (driver_register+0xa8/0x134) from [<c0050550>](do_one_initcall+0xcc/0x1a4)
> [<c0050550>] (do_one_initcall+0xcc/0x1a4) from [<c00084e4>](kernel_init+0x14c/0x214)
> [<c00084e4>] (kernel_init+0x14c/0x214) from [<c005b494>](kernel_thread_exit+0x0/0x8)
> ---[ end trace 4053287f8a5ec18f ]---
>
> Also rearrange ads7846_setup_pendown() to have only one exit point
> returning success.
>
> Reported-by: Sourav Poddar <sourav.poddar at ti.com>
> Signed-off-by: Dmitry Torokhov <dtor at mail.ru>
> ---
>
> drivers/input/touchscreen/ads7846.c | 39 ++++++++++++++++++++---------------
> 1 files changed, 22 insertions(+), 17 deletions(-)
>
>
> diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
> index 0e9492d..b1217e1 100644
> --- a/drivers/input/touchscreen/ads7846.c
> +++ b/drivers/input/touchscreen/ads7846.c
> @@ -946,30 +946,30 @@ static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads784
> struct ads7846_platform_data *pdata = spi->dev.platform_data;
> int err;
>
> - /* REVISIT when the irq can be triggered active-low, or if for some
> + /*
> + * REVISIT when the irq can be triggered active-low, or if for some
> * reason the touchscreen isn't hooked up, we don't need to access
> * the pendown state.
> */
> - if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
> - dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
> - return -EINVAL;
> - }
>
> if (pdata->get_pendown_state) {
> ts->get_pendown_state = pdata->get_pendown_state;
> - return 0;
> - }
> + } else if (gpio_is_valid(pdata->gpio_pendown)) {
> +
> + err = gpio_request_one(pdata->gpio_pendown, GPIOF_DIR_IN,
> + "ads7846_pendown");
> + if (err) {
> + dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
> + pdata->gpio_pendown);
> + return err;
> + }
>
> - err = gpio_request_one(pdata->gpio_pendown, GPIOF_DIR_IN,
> - "ads7846_pendown");
> - if (err) {
> - dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
> - pdata->gpio_pendown);
> - return err;
> + ts->gpio_pendown = pdata->gpio_pendown;
> + } else {
> + dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
> + return -EINVAL;
> }
>
> - ts->gpio_pendown = pdata->gpio_pendown;
> -
> return 0;
> }
>
> @@ -1359,7 +1359,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
> err_put_regulator:
> regulator_put(ts->reg);
> err_free_gpio:
> - if (ts->gpio_pendown != -1)
> + if (!ts->get_pendown_state)
> gpio_free(ts->gpio_pendown);
> err_cleanup_filter:
> if (ts->filter_cleanup)
> @@ -1389,8 +1389,13 @@ static int __devexit ads7846_remove(struct spi_device *spi)
> regulator_disable(ts->reg);
> regulator_put(ts->reg);
>
> - if (ts->gpio_pendown != -1)
> + if (!ts->get_pendown_state) {
> + /*
> + * If we are not using specialized pendown method we must
> + * have been relying on gpio we set up ourselves.
> + */
> gpio_free(ts->gpio_pendown);
> + }
>
> if (ts->filter_cleanup)
> ts->filter_cleanup(ts->filter_data);
> --
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