From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v3 2/2] Input: ads7846: use gpio_request_one to configure pendown_gpio Date: Thu, 3 Feb 2011 09:19:53 -0800 Message-ID: <20110203171953.GA13997@core.coreip.homeip.net> References: <1296746506-12221-1-git-send-email-sourav.poddar@ti.com> <20110203165405.GB12802@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20110203165405.GB12802@core.coreip.homeip.net> Sender: linux-omap-owner@vger.kernel.org To: Sourav Poddar Cc: LW@karo-electronics.de, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-input@vger.kernel.org, gadiyar@ti.com, charu@ti.com, grinberg@compulab.co.il, balbi@ti.com List-Id: linux-input@vger.kernel.org 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 > > Cc: Dmitry Torokhov > > 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. -- Dmitry Input: ads7846 - check proper condition when freeing gpio From: Dmitry Torokhov 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: [] (unwind_backtrace+0x0/0xe4) from [](warn_slowpath_common+0x4c/0x64) [] (warn_slowpath_common+0x4c/0x64) from [](warn_slowpath_null+0x18/0x1c) [] (warn_slowpath_null+0x18/0x1c) from [](gpio_free+0x100/0x12c) [] (gpio_free+0x100/0x12c) from [](ads7846_probe+0xa38/0xc5c) [] (ads7846_probe+0xa38/0xc5c) from [](spi_drv_probe+0x18/0x1c) [] (spi_drv_probe+0x18/0x1c) from [](driver_probe_device+0xc8/0x184) [] (driver_probe_device+0xc8/0x184) from [](__driver_attach+0x68/0x8c) [] (__driver_attach+0x68/0x8c) from [](bus_for_each_dev+0x48/0x74) [] (bus_for_each_dev+0x48/0x74) from [](bus_add_driver+0xa0/0x220) [] (bus_add_driver+0xa0/0x220) from [](driver_register+0xa8/0x134) [] (driver_register+0xa8/0x134) from [](do_one_initcall+0xcc/0x1a4) [] (do_one_initcall+0xcc/0x1a4) from [](kernel_init+0x14c/0x214) [] (kernel_init+0x14c/0x214) from [](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 Signed-off-by: Dmitry Torokhov --- 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);