Hi again, On 02/03/11 12:10, Igor Grinberg wrote:
> 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>} Sorry for the above links (this is embarrassing, but I've got played by my email client), I meant of course: if (pdata->get_pendown_state) { ts->get_pendown_state = pdata->get_pendown_state; ts->gpio_pendown = -1; return 0; } > > 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
