Hi, On 02/03/11 11:48, Sourav Poddar wrote:
> gpio_pendown in ads7846_probe is not getting initalized (defaulted to 0) > resulting in gpio_free to be called without a gpio_request. This > results in the following backtrace in bootup. > > ------------[ 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 ]--- > > Initializing gpio_pendown in ads7846_probe to -1 before > ads7846_setup_pendown function removes the above backtrace > warning. > > Signed-off-by: Sourav Poddar <[email protected]> > Signed-off-by: Kishon Vijay Abraham I <[email protected]> > --- > drivers/input/touchscreen/ads7846.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/drivers/input/touchscreen/ads7846.c > b/drivers/input/touchscreen/ads7846.c > index 14ea54b..036f245 100644 > --- a/drivers/input/touchscreen/ads7846.c > +++ b/drivers/input/touchscreen/ads7846.c > @@ -1221,6 +1221,7 @@ static int __devinit ads7846_probe(struct spi_device > *spi) > ts->input = input_dev; > ts->vref_mv = pdata->vref_mv; > ts->swap_xy = pdata->swap_xy; > + ts->gpio_pendown = -1; Wouldn't it be better putting this into ads7846_setup_pendown() function? This will keep the whole gpio_pendown initialization code close together. Something like: if (pdata->get_pendown_state) { <http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=drivers/input/touchscreen/ads7846.c;h=14ea54b78e4648b0ac8a3403440f6f5d120dfdd9;hb=HEAD#l954> ts->get_pendown_state = pdata->get_pendown_state; ts->gpio_pendown = -1; <http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=drivers/input/touchscreen/ads7846.c;h=14ea54b78e4648b0ac8a3403440f6f5d120dfdd9;hb=HEAD#l955> return 0; <http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=drivers/input/touchscreen/ads7846.c;h=14ea54b78e4648b0ac8a3403440f6f5d120dfdd9;hb=HEAD#l956>} Also, why don't we use -EINVAL for the invalid gpio number instead of -1 constant? > > mutex_init(&ts->lock); > init_waitqueue_head(&ts->wait); -- Regards, Igor. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
