| Message ID | 000b01cdd1e0$293f0d90$7bbd28b0$%han@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 04 Dec 2012 14:28:15 +0900 Jingoo Han <jg1.han@samsung.com> wrote: > From: Marko Katic <dromede@gmail.com> > > Changing backlight intensity on an Akita (Sharp Zaurus C-1000) > triggers WARN_ON message: Well, I queued it up. > ... > > --- a/drivers/video/backlight/corgi_lcd.c > +++ b/drivers/video/backlight/corgi_lcd.c > @@ -408,11 +408,20 @@ static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity) > /* Bit 5 via GPIO_BACKLIGHT_CONT */ > cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted; > > - if (gpio_is_valid(lcd->gpio_backlight_cont)) > - gpio_set_value(lcd->gpio_backlight_cont, cont); > + if (gpio_is_valid(lcd->gpio_backlight_cont)) { > + if (gpio_cansleep(lcd->gpio_backlight_cont)) > + gpio_set_value_cansleep(lcd->gpio_backlight_cont, cont); > + else > + gpio_set_value(lcd->gpio_backlight_cont, cont); > + } But this looks utterly daft. Grant, these two things are the same - do we need both of them?
On Tue, Dec 4, 2012 at 6:28 AM, Jingoo Han <jg1.han@samsung.com> wrote: > From: Marko Katic <dromede@gmail.com> > > Changing backlight intensity on an Akita (Sharp Zaurus C-1000) > triggers WARN_ON message: > > WARNING: at drivers/gpio/gpiolib.c:1672 __gpio_set_value+0x38/0xa4() > Modules linked in: > Backtrace: > [<c000c0ac>] (dump_backtrace+0x0/0x110) from [<c02c8278>] (dump_stack+0x18/0x1c) > r6:c0158fc8 r5:00000009 r4:00000000 r3:c03d4f70 > [<c02c8260>] (dump_stack+0x0/0x1c) from [<c0019194>] (warn_slowpath_common+0x54/0x6c) > [<c0019140>] (warn_slowpath_common+0x0/0x6c) from [<c00191d0>] (warn_slowpath_null+0x24/0x2c) > r8:c38d5c00 r7:c03f82c0 r6:00000000 r5:000000d0 r4:c384e4fc > r3:00000009 > [<c00191ac>] (warn_slowpath_null+0x0/0x2c) from [<c0158fc8>] (__gpio_set_value+0x38/0xa4) > [<c0158f90>] (__gpio_set_value+0x0/0xa4) from [<c0169b4c>] (corgi_bl_set_intensity+0x44/0x74) > r7:c3933418 r6:c3933400 r5:c392cdf0 r4:0000002f > [<c0169b08>] (corgi_bl_set_intensity+0x0/0x74) from [<c0169c1c>] (corgi_bl_update_status+0x5c/0x64) > r5:c03d31f0 r4:c3933400 > [<c0169bc0>] (corgi_bl_update_status+0x0/0x64) from [<c02c3a68>] (corgi_lcd_probe+0x1a8/0x258) > r4:c392cdf0 r3:c0169bc0 > [<c02c38c0>] (corgi_lcd_probe+0x0/0x258) from [<c01da7a4>] (spi_drv_probe+0x20/0x24) > r8:00000052 r7:c0192d9c r6:c03da6e8 r5:c38d5c34 r4:c38d5c00 > [<c01da784>] (spi_drv_probe+0x0/0x24) from [<c0192c44>] (driver_probe_device+0xb0/0x208) > [<c0192b94>] (driver_probe_device+0x0/0x208) from [<c0192e0c>] (__driver_attach+0x70/0x94) > r6:c03da6e8 r5:c38d5c34 r4:c38d5c00 r3:00000000 > [<c0192d9c>] (__driver_attach+0x0/0x94) from [<c0191268>] (bus_for_each_dev+0x54/0x90) > r6:c03da6e8 r5:c3827e80 r4:00000000 r3:00000000 > [<c0191214>] (bus_for_each_dev+0x0/0x90) from [<c01927a4>] (driver_attach+0x20/0x28) > r7:00000000 r6:c03e29ec r5:c3932980 r4:c03da6e8 > [<c0192784>] (driver_attach+0x0/0x28) from [<c0192340>] (bus_add_driver+0xd4/0x22c) > [<c019226c>] (bus_add_driver+0x0/0x22c) from [<c019335c>] (driver_register+0xa4/0x134) > r8:00000052 r7:c03ea900 r6:c03c32ac r5:c03bdfc8 r4:c03da6e8 > [<c01932b8>] (driver_register+0x0/0x134) from [<c01db7ec>] (spi_register_driver+0x4c/0x60) > [<c01db7a0>] (spi_register_driver+0x0/0x60) from [<c03b3ce0>] (corgi_lcd_driver_init+0x14/0x1c) > [<c03b3ccc>] (corgi_lcd_driver_init+0x0/0x1c) from [<c000868c>] (do_one_initcall+0x9c/0x174) > [<c00085f0>] (do_one_initcall+0x0/0x174) from [<c02c1b94>] (kernel_init+0xf4/0x2a8) > [<c02c1aa0>] (kernel_init+0x0/0x2a8) from [<c0009270>] (ret_from_fork+0x14/0x24) > ---[ end trace a863a63f242ee38c ]--- > > Akita machines have backlight controls hooked to a gpio expander chip, > max7310. In this case, pca953x_gpio_set_value() can be called to control > gpio, and pca953x_setup_gpio() sets can_sleep flag. Therefore, > gpio_set_value_cansleep() should be used in order to avoid WARN_ON on > akita machines. > > Akita is the only exception in this case since other users of corgi_lcd > access backlight gpio controls through a different gpio expander such as > max7310 which does not set the can_sleep flag. I think you forgot to delete "such as max7310". Akita has the max7310, all the other models have a different expander. > > [jg1.han@samsung.com: used gpio_cansleep()] > Signed-off-by: Marko Katic <dromede@gmail.com> > Signed-off-by: Jingoo Han <jg1.han@samsung.com> > --- > drivers/video/backlight/corgi_lcd.c | 17 +++++++++++++---- > 1 files changed, 13 insertions(+), 4 deletions(-) > > diff --git a/drivers/video/backlight/corgi_lcd.c b/drivers/video/backlight/corgi_lcd.c > index e2e1b62..e5168f4 100644 > --- a/drivers/video/backlight/corgi_lcd.c > +++ b/drivers/video/backlight/corgi_lcd.c > @@ -408,11 +408,20 @@ static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity) > /* Bit 5 via GPIO_BACKLIGHT_CONT */ > cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted; > > - if (gpio_is_valid(lcd->gpio_backlight_cont)) > - gpio_set_value(lcd->gpio_backlight_cont, cont); > + if (gpio_is_valid(lcd->gpio_backlight_cont)) { > + if (gpio_cansleep(lcd->gpio_backlight_cont)) > + gpio_set_value_cansleep(lcd->gpio_backlight_cont, cont); > + else > + gpio_set_value(lcd->gpio_backlight_cont, cont); > + } > > - if (gpio_is_valid(lcd->gpio_backlight_on)) > - gpio_set_value(lcd->gpio_backlight_on, intensity); > + if (gpio_is_valid(lcd->gpio_backlight_on)) { > + if (gpio_cansleep(lcd->gpio_backlight_on)) > + gpio_set_value_cansleep(lcd->gpio_backlight_on, > + intensity); > + else > + gpio_set_value(lcd->gpio_backlight_on, intensity); > + } > > if (lcd->kick_battery) > lcd->kick_battery(); > -- > 1.7.2.5 > >
On Wednesday, December 05, 2012 8:28 AM, Marko Katic wrote > On Tue, Dec 4, 2012 at 6:28 AM, Jingoo Han <jg1.han@samsung.com> wrote: > > From: Marko Katic <dromede@gmail.com> > > > > Changing backlight intensity on an Akita (Sharp Zaurus C-1000) > > triggers WARN_ON message: > > > > WARNING: at drivers/gpio/gpiolib.c:1672 __gpio_set_value+0x38/0xa4() > > Modules linked in: > > Backtrace: > > [<c000c0ac>] (dump_backtrace+0x0/0x110) from [<c02c8278>] (dump_stack+0x18/0x1c) > > r6:c0158fc8 r5:00000009 r4:00000000 r3:c03d4f70 > > [<c02c8260>] (dump_stack+0x0/0x1c) from [<c0019194>] (warn_slowpath_common+0x54/0x6c) > > [<c0019140>] (warn_slowpath_common+0x0/0x6c) from [<c00191d0>] (warn_slowpath_null+0x24/0x2c) > > r8:c38d5c00 r7:c03f82c0 r6:00000000 r5:000000d0 r4:c384e4fc > > r3:00000009 > > [<c00191ac>] (warn_slowpath_null+0x0/0x2c) from [<c0158fc8>] (__gpio_set_value+0x38/0xa4) > > [<c0158f90>] (__gpio_set_value+0x0/0xa4) from [<c0169b4c>] (corgi_bl_set_intensity+0x44/0x74) > > r7:c3933418 r6:c3933400 r5:c392cdf0 r4:0000002f > > [<c0169b08>] (corgi_bl_set_intensity+0x0/0x74) from [<c0169c1c>] (corgi_bl_update_status+0x5c/0x64) > > r5:c03d31f0 r4:c3933400 > > [<c0169bc0>] (corgi_bl_update_status+0x0/0x64) from [<c02c3a68>] (corgi_lcd_probe+0x1a8/0x258) > > r4:c392cdf0 r3:c0169bc0 > > [<c02c38c0>] (corgi_lcd_probe+0x0/0x258) from [<c01da7a4>] (spi_drv_probe+0x20/0x24) > > r8:00000052 r7:c0192d9c r6:c03da6e8 r5:c38d5c34 r4:c38d5c00 > > [<c01da784>] (spi_drv_probe+0x0/0x24) from [<c0192c44>] (driver_probe_device+0xb0/0x208) > > [<c0192b94>] (driver_probe_device+0x0/0x208) from [<c0192e0c>] (__driver_attach+0x70/0x94) > > r6:c03da6e8 r5:c38d5c34 r4:c38d5c00 r3:00000000 > > [<c0192d9c>] (__driver_attach+0x0/0x94) from [<c0191268>] (bus_for_each_dev+0x54/0x90) > > r6:c03da6e8 r5:c3827e80 r4:00000000 r3:00000000 > > [<c0191214>] (bus_for_each_dev+0x0/0x90) from [<c01927a4>] (driver_attach+0x20/0x28) > > r7:00000000 r6:c03e29ec r5:c3932980 r4:c03da6e8 > > [<c0192784>] (driver_attach+0x0/0x28) from [<c0192340>] (bus_add_driver+0xd4/0x22c) > > [<c019226c>] (bus_add_driver+0x0/0x22c) from [<c019335c>] (driver_register+0xa4/0x134) > > r8:00000052 r7:c03ea900 r6:c03c32ac r5:c03bdfc8 r4:c03da6e8 > > [<c01932b8>] (driver_register+0x0/0x134) from [<c01db7ec>] (spi_register_driver+0x4c/0x60) > > [<c01db7a0>] (spi_register_driver+0x0/0x60) from [<c03b3ce0>] (corgi_lcd_driver_init+0x14/0x1c) > > [<c03b3ccc>] (corgi_lcd_driver_init+0x0/0x1c) from [<c000868c>] (do_one_initcall+0x9c/0x174) > > [<c00085f0>] (do_one_initcall+0x0/0x174) from [<c02c1b94>] (kernel_init+0xf4/0x2a8) > > [<c02c1aa0>] (kernel_init+0x0/0x2a8) from [<c0009270>] (ret_from_fork+0x14/0x24) > > ---[ end trace a863a63f242ee38c ]--- > > > > Akita machines have backlight controls hooked to a gpio expander chip, > > max7310. In this case, pca953x_gpio_set_value() can be called to control > > gpio, and pca953x_setup_gpio() sets can_sleep flag. Therefore, > > gpio_set_value_cansleep() should be used in order to avoid WARN_ON on > > akita machines. > > > > Akita is the only exception in this case since other users of corgi_lcd > > access backlight gpio controls through a different gpio expander such as > > max7310 which does not set the can_sleep flag. > > I think you forgot to delete "such as max7310". Akita has > the max7310, all the other models have a different expander. Yes, you're right. I added an unnecessary word, 'such as max7310'. It should be deleted. I will send v4 patch, soon. Best regards, Jingoo Han > > > > > [jg1.han@samsung.com: used gpio_cansleep()] > > Signed-off-by: Marko Katic <dromede@gmail.com> > > Signed-off-by: Jingoo Han <jg1.han@samsung.com> > > --- > > drivers/video/backlight/corgi_lcd.c | 17 +++++++++++++---- > > 1 files changed, 13 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/video/backlight/corgi_lcd.c b/drivers/video/backlight/corgi_lcd.c > > index e2e1b62..e5168f4 100644 > > --- a/drivers/video/backlight/corgi_lcd.c > > +++ b/drivers/video/backlight/corgi_lcd.c > > @@ -408,11 +408,20 @@ static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity) > > /* Bit 5 via GPIO_BACKLIGHT_CONT */ > > cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted; > > > > - if (gpio_is_valid(lcd->gpio_backlight_cont)) > > - gpio_set_value(lcd->gpio_backlight_cont, cont); > > + if (gpio_is_valid(lcd->gpio_backlight_cont)) { > > + if (gpio_cansleep(lcd->gpio_backlight_cont)) > > + gpio_set_value_cansleep(lcd->gpio_backlight_cont, cont); > > + else > > + gpio_set_value(lcd->gpio_backlight_cont, cont); > > + } > > > > - if (gpio_is_valid(lcd->gpio_backlight_on)) > > - gpio_set_value(lcd->gpio_backlight_on, intensity); > > + if (gpio_is_valid(lcd->gpio_backlight_on)) { > > + if (gpio_cansleep(lcd->gpio_backlight_on)) > > + gpio_set_value_cansleep(lcd->gpio_backlight_on, > > + intensity); > > + else > > + gpio_set_value(lcd->gpio_backlight_on, intensity); > > + } > > > > if (lcd->kick_battery) > > lcd->kick_battery(); > > -- > > 1.7.2.5 > > > >
On Wednesday, December 05, 2012 7:58 AM, Andrew Morton wrote > On Tue, 04 Dec 2012 14:28:15 +0900 > Jingoo Han <jg1.han@samsung.com> wrote: > > > From: Marko Katic <dromede@gmail.com> > > > > Changing backlight intensity on an Akita (Sharp Zaurus C-1000) > > triggers WARN_ON message: > > Well, I queued it up. > > > ... > > > > --- a/drivers/video/backlight/corgi_lcd.c > > +++ b/drivers/video/backlight/corgi_lcd.c > > @@ -408,11 +408,20 @@ static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity) > > /* Bit 5 via GPIO_BACKLIGHT_CONT */ > > cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted; > > > > - if (gpio_is_valid(lcd->gpio_backlight_cont)) > > - gpio_set_value(lcd->gpio_backlight_cont, cont); > > + if (gpio_is_valid(lcd->gpio_backlight_cont)) { > > + if (gpio_cansleep(lcd->gpio_backlight_cont)) > > + gpio_set_value_cansleep(lcd->gpio_backlight_cont, cont); > > + else > > + gpio_set_value(lcd->gpio_backlight_cont, cont); > > + } > > But this looks utterly daft. Grant, these two things are the same - do > we need both of them? Hi Andrew, There is another difference, except for warning message. There is might_sleep_if(extra_checks) in gpio_set_value_cansleep(). Also, I saw the Documentation/gpio.txt as below: 172 /* GPIO OUTPUT */ 173 void gpio_set_value(unsigned gpio, int value); ... 213 /* GPIO OUTPUT, might sleep */ 214 void gpio_set_value_cansleep(unsigned gpio, int value); Best regards, Jingoo Han
diff --git a/drivers/video/backlight/corgi_lcd.c b/drivers/video/backlight/corgi_lcd.c index e2e1b62..e5168f4 100644 --- a/drivers/video/backlight/corgi_lcd.c +++ b/drivers/video/backlight/corgi_lcd.c @@ -408,11 +408,20 @@ static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity) /* Bit 5 via GPIO_BACKLIGHT_CONT */ cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted; - if (gpio_is_valid(lcd->gpio_backlight_cont)) - gpio_set_value(lcd->gpio_backlight_cont, cont); + if (gpio_is_valid(lcd->gpio_backlight_cont)) { + if (gpio_cansleep(lcd->gpio_backlight_cont)) + gpio_set_value_cansleep(lcd->gpio_backlight_cont, cont); + else + gpio_set_value(lcd->gpio_backlight_cont, cont); + } - if (gpio_is_valid(lcd->gpio_backlight_on)) - gpio_set_value(lcd->gpio_backlight_on, intensity); + if (gpio_is_valid(lcd->gpio_backlight_on)) { + if (gpio_cansleep(lcd->gpio_backlight_on)) + gpio_set_value_cansleep(lcd->gpio_backlight_on, + intensity); + else + gpio_set_value(lcd->gpio_backlight_on, intensity); + } if (lcd->kick_battery) lcd->kick_battery();