On Fri, Mar 13, 2015 at 04:30:43PM +0200, Ville Syrjälä wrote:
> On Thu, Mar 12, 2015 at 10:01:33PM +0530, Shobhit Kumar wrote:
> > CC: Samuel Ortiz <sa...@linux.intel.com>
> > Cc: Linus Walleij <linus.wall...@linaro.org>
> > Cc: Alexandre Courbot <gnu...@gmail.com>
> > Cc: Thierry Reding <thierry.red...@gmail.com>
> > Signed-off-by: Shobhit Kumar <shobhit.ku...@intel.com>
> > ---
> > drivers/gpu/drm/i915/intel_dsi.c | 25 +++++++++++++++++++++++++
> > drivers/gpu/drm/i915/intel_dsi.h | 3 +++
> > 2 files changed, 28 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_dsi.c
> > b/drivers/gpu/drm/i915/intel_dsi.c
> > index 219421c..511446f 100644
> > --- a/drivers/gpu/drm/i915/intel_dsi.c
> > +++ b/drivers/gpu/drm/i915/intel_dsi.c
> > @@ -32,6 +32,7 @@
> > #include <drm/drm_mipi_dsi.h>
> > #include <linux/slab.h>
> > #include <linux/gpio/consumer.h>
> > +#include <linux/pwm.h>
> > #include "i915_drv.h"
> > #include "intel_drv.h"
> > #include "intel_dsi.h"
> > @@ -402,6 +403,10 @@ static void intel_dsi_enable(struct intel_encoder
> > *encoder)
> >
> > intel_dsi_port_enable(encoder);
> > }
> > +
> > + /* Enable the backlight with default PWM as programmed by BIOS */
> > + pwm_enable(intel_dsi->pwm);
> > + pwm_config_alternate(intel_dsi->pwm, 0x7F, 100);
>
> I suppose we migth want to wrap these in 'if (intel_dsi->pwm)' checks,
> or does the pwm subsystem take care of NULL checks for us?
>
> > }
> >
> > static void intel_dsi_pre_enable(struct intel_encoder *encoder)
> > @@ -467,6 +472,11 @@ static void intel_dsi_pre_disable(struct intel_encoder
> > *encoder)
> >
> > DRM_DEBUG_KMS("\n");
> >
> > + /* Disable the backlight */
> > + pwm_config_alternate(intel_dsi->pwm, 0x7F, 0);
> > + usleep_range(2000, 3000);
> > + pwm_disable(intel_dsi->pwm);
>
> ditto
>
> > +
> > if (is_vid_mode(intel_dsi)) {
> > /* Send Shutdown command to the panel in LP mode */
> > for_each_dsi_port(port, intel_dsi->ports)
> > @@ -971,6 +981,10 @@ static void intel_dsi_encoder_destroy(struct
> > drm_encoder *encoder)
> > if (intel_dsi->gpio_panel)
> > gpiod_put(intel_dsi->gpio_panel);
> >
> > + /* dispose of the pwm */
> > + if (intel_dsi->pwm)
> > + pwm_put(intel_dsi->pwm);
> > +
> > intel_encoder_destroy(encoder);
> > }
> >
> > @@ -1098,6 +1112,17 @@ void intel_dsi_init(struct drm_device *dev)
> > DRM_ERROR("Failed to own gpio for panel control\n");
> > intel_dsi->gpio_panel = NULL;
> > }
> > +
> > + /* Get the PWM chip for backlight control */
> > + intel_dsi->pwm = pwm_get(dev->dev, "pwm_backlight");
> > + if (IS_ERR(intel_dsi->pwm)) {
> > + DRM_ERROR("Faild to own the pwm chip\n");
> > + intel_dsi->pwm = NULL;
If the i915.ko driver loads before the mfd.ko driver we need to do a
deferred probe here I think. Just failing isn't robust.
This also means that if people don't configure their kernel properly then
we'll fall over here, but meh.
-Daniel
> > + } else if (pwm_config_alternate(intel_dsi->pwm, 0x7F, 100) < 0)
> > {
> > + DRM_ERROR("Failed to configure the pwm chip\n");
> > + pwm_put(intel_dsi->pwm);
> > + intel_dsi->pwm = NULL;
> > + }
> > }
> >
> > intel_encoder->type = INTEL_OUTPUT_DSI;
> > diff --git a/drivers/gpu/drm/i915/intel_dsi.h
> > b/drivers/gpu/drm/i915/intel_dsi.h
> > index 8be75a7..d8ec9c1 100644
> > --- a/drivers/gpu/drm/i915/intel_dsi.h
> > +++ b/drivers/gpu/drm/i915/intel_dsi.h
> > @@ -52,6 +52,9 @@ struct intel_dsi {
> > /* GPIO Desc for CRC based Panel control */
> > struct gpio_desc *gpio_panel;
> >
> > + /* PWM chip */
> > + struct pwm_device *pwm;
> > +
> > struct intel_connector *attached_connector;
> >
> > /* bit mask of ports being driven */
> > --
> > 2.1.0
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
> --
> Ville Syrjälä
> Intel OTC
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
