Re: [PATCH v6 2/3] drm: bridge: Add thc63lvd1024 LVDS decoder driver

[jacopo mondi <jacopo@jmondi.org>]

HI Vladimir,

On Tue, Mar 27, 2018 at 09:24:28AM +0300, Vladimir Zapolskiy wrote:
> Hi Jacopo,
>
> On 03/16/2018 05:16 PM, Jacopo Mondi wrote:
> > Add DRM bridge driver for Thine THC63LVD1024 LVDS to digital parallel
> > output converter.
> >
> > Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> > Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
> > Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/gpu/drm/bridge/Kconfig        |   6 +
> >  drivers/gpu/drm/bridge/Makefile       |   1 +
> >  drivers/gpu/drm/bridge/thc63lvd1024.c | 255 ++++++++++++++++++++++++++++++++++
> >  3 files changed, 262 insertions(+)
> >  create mode 100644 drivers/gpu/drm/bridge/thc63lvd1024.c
> >
> > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> > index 3b99d5a..5815a20 100644
> > --- a/drivers/gpu/drm/bridge/Kconfig
> > +++ b/drivers/gpu/drm/bridge/Kconfig
> > @@ -92,6 +92,12 @@ config DRM_SII9234
> >  	  It is an I2C driver, that detects connection of MHL bridge
> >  	  and starts encapsulation of HDMI signal.
> >
> > +config DRM_THINE_THC63LVD1024
> > +	tristate "Thine THC63LVD1024 LVDS decoder bridge"
> > +	depends on OF
> > +	---help---
> > +	  Thine THC63LVD1024 LVDS/parallel converter driver.
> > +
> >  config DRM_TOSHIBA_TC358767
> >  	tristate "Toshiba TC358767 eDP bridge"
> >  	depends on OF
> > diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> > index 373eb28..fd90b16 100644
> > --- a/drivers/gpu/drm/bridge/Makefile
> > +++ b/drivers/gpu/drm/bridge/Makefile
> > @@ -8,6 +8,7 @@ obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
> >  obj-$(CONFIG_DRM_SIL_SII8620) += sil-sii8620.o
> >  obj-$(CONFIG_DRM_SII902X) += sii902x.o
> >  obj-$(CONFIG_DRM_SII9234) += sii9234.o
> > +obj-$(CONFIG_DRM_THINE_THC63LVD1024) += thc63lvd1024.o
> >  obj-$(CONFIG_DRM_TOSHIBA_TC358767) += tc358767.o
> >  obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
> >  obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
> > diff --git a/drivers/gpu/drm/bridge/thc63lvd1024.c b/drivers/gpu/drm/bridge/thc63lvd1024.c
> > new file mode 100644
> > index 0000000..02a54c2
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/thc63lvd1024.c
> > @@ -0,0 +1,255 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * THC63LVD1024 LVDS to parallel data DRM bridge driver.
> > + *
> > + * Copyright (C) 2018 Jacopo Mondi <jacopo+renesas@jmondi.org>
> > + */
> > +
> > +#include <drm/drmP.h>
> > +#include <drm/drm_bridge.h>
> > +#include <drm/drm_panel.h>
> > +
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/regulator/consumer.h>
> > +
> > +enum {
> > +	THC63_LVDS_IN0,
> > +	THC63_LVDS_IN1,
> > +	THC63_DIGITAL_OUT0,
> > +	THC63_DIGITAL_OUT1,
> > +};
> > +
> > +static const char * const thc63_reg_names[] = {
> > +	"vcc", "lvcc", "pvcc", "cvcc",
> > +};
> > +
> > +struct thc63_dev {
> > +	struct device *dev;
> > +
> > +	struct regulator *vccs[ARRAY_SIZE(thc63_reg_names)];
> > +
> > +	struct gpio_desc *pdwn;
> > +	struct gpio_desc *oe;
> > +
> > +	struct drm_bridge bridge;
> > +	struct drm_bridge *next;
> > +};
> > +
> > +static inline struct thc63_dev *to_thc63(struct drm_bridge *bridge)
> > +{
> > +	return container_of(bridge, struct thc63_dev, bridge);
> > +}
> > +
> > +static int thc63_attach(struct drm_bridge *bridge)
> > +{
> > +	struct thc63_dev *thc63 = to_thc63(bridge);
> > +
> > +	return drm_bridge_attach(bridge->encoder, thc63->next, bridge);
> > +}
> > +
> > +static void thc63_enable(struct drm_bridge *bridge)
> > +{
> > +	struct thc63_dev *thc63 = to_thc63(bridge);
> > +	struct regulator *vcc;
> > +	int i;
>
> unsigned int i;
>
> > +
> > +	for (i = 0; i < ARRAY_SIZE(thc63->vccs); i++) {
> > +		vcc = thc63->vccs[i];
> > +		if (!vcc)
> > +			continue;
> > +
> > +		if (regulator_enable(vcc))
> > +			goto error_vcc_enable;
> > +	}
> > +
> > +	if (thc63->pdwn)
> > +		gpiod_set_value(thc63->pdwn, 0);
> > +
> > +	if (thc63->oe)
> > +		gpiod_set_value(thc63->oe, 1);
> > +
> > +	return;
> > +
> > +error_vcc_enable:
> > +	dev_err(thc63->dev, "Failed to enable regulator %s\n",
> > +		thc63_reg_names[i]);
> > +
> > +	for (i = i - 1; i >= 0; i--) {
> > +		vcc = thc63->vccs[i];
> > +		if (!vcc)
> > +			continue;
> > +
> > +		regulator_disable(vcc);
> > +	}
> > +}
> > +
> > +static void thc63_disable(struct drm_bridge *bridge)
> > +{
> > +	struct thc63_dev *thc63 = to_thc63(bridge);
> > +	struct regulator *vcc;
> > +	int i;
> > +
> > +	if (thc63->oe)
> > +		gpiod_set_value(thc63->oe, 0);
> > +
> > +	if (thc63->pdwn)
> > +		gpiod_set_value(thc63->pdwn, 1);
> > +
> > +	for (i = ARRAY_SIZE(thc63->vccs) - 1; i >= 0; i--) {
> > +		vcc = thc63->vccs[i];
> > +		if (!vcc)
> > +			continue;
> > +
> > +		if (regulator_disable(vcc))
> > +			dev_dbg(thc63->dev,
> > +				"Failed to disable regulator %s\n",
> > +				thc63_reg_names[i]);
> > +	}
> > +}
> > +
> > +struct drm_bridge_funcs thc63_bridge_func = {
>
> Apparently you missed all my comments from v2 review.
>
I did not :)
v6 was already out when you commented on v2..

> If you like to avoid non-NULL function pointers to the void, please
> use static const storage qualifier.
>
> --
> With best wishes,
> Vladimir