[PATCH 2/5] drm/exynos: use regmap interface to set hdmiphy control bit in pmu

[Rahul Sharma]

On 11 April 2014 07:22, Rahul Sharma <r.sh.open at gmail.com> wrote:
> Thanks Tomasz,
>
> This patch is not longer required after rebasing to Tomasz Stanislawski's
> Simple Phy patches.
>

Hi All,

We had further discussion on the "Simple Phy Driver" at
http://www.spinics.net/lists/linux-samsung-soc/msg31100.html. The
discussion went in favor of the use of regmap interface.

As many other drivers are already using regmap interfaces for the same
purpose, it would also be consistent to use PMU syscon handle to control
phy enable bit in the hdmi driver. I will address the pending comments from
Tomasz Figa and post the next version of this patch.

Please let me know if any concern.

Regards,
Rahul Sharma

> Regards,
> Rahul Sharma.
>
> On 10 April 2014 22:30, Tomasz Figa <t.figa at samsung.com> wrote:
>> Hi Rahul,
>>
>> On 02.04.2014 19:13, Rahul Sharma wrote:
>>>
>>> From: Rahul Sharma <Rahul.Sharma at samsung.com>
>>>
>>> Hdmiphy control bit needs to be set before setting the resolution
>>> to hdmi hardware. This was handled using dummy hdmiphy clock which
>>> is removed now.
>>>
>>> PMU is already defined as system controller for exynos SoC. Registers
>>> of PMU are accessed using regmap interfaces.
>>>
>>> Devicetree binding document for hdmi is also updated.
>>>
>>> Signed-off-by: Rahul Sharma <Rahul.Sharma at samsung.com>
>>> ---
>>>   .../devicetree/bindings/video/exynos_hdmi.txt      |    2 ++
>>>   drivers/gpu/drm/exynos/exynos_hdmi.c               |   17
>>> +++++++++++++++++
>>>   drivers/gpu/drm/exynos/regs-hdmi.h                 |    4 ++++
>>>   3 files changed, 23 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/video/exynos_hdmi.txt
>>> b/Documentation/devicetree/bindings/video/exynos_hdmi.txt
>>> index f9187a2..243a499 100644
>>> --- a/Documentation/devicetree/bindings/video/exynos_hdmi.txt
>>> +++ b/Documentation/devicetree/bindings/video/exynos_hdmi.txt
>>> @@ -27,6 +27,7 @@ Required properties:
>>>         "hdmi", "sclk_hdmi", "sclk_pixel", "sclk_hdmiphy" and "mout_hdmi".
>>>   - ddc: phandle to the hdmi ddc node
>>>   - phy: phandle to the hdmi phy node
>>> +- samsung,syscon-phandle: phandle for system controller node for PMU.
>>>
>>>   Example:
>>>
>>> @@ -37,4 +38,5 @@ Example:
>>>                 hpd-gpio = <&gpx3 7 1>;
>>>                 ddc = <&hdmi_ddc_node>;
>>>                 phy = <&hdmi_phy_node>;
>>> +               samsung,syscon-phandle = <&pmu_system_controller>;
>>>         };
>>> diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c
>>> b/drivers/gpu/drm/exynos/exynos_hdmi.c
>>> index 23abfa0..47b8c06 100644
>>> --- a/drivers/gpu/drm/exynos/exynos_hdmi.c
>>> +++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
>>> @@ -36,6 +36,8 @@
>>>   #include <linux/i2c.h>
>>>   #include <linux/of_gpio.h>
>>>   #include <linux/hdmi.h>
>>> +#include <linux/mfd/syscon.h>
>>> +#include <linux/regmap.h>
>>>
>>>   #include <drm/exynos_drm.h>
>>>
>>> @@ -194,6 +196,7 @@ struct hdmi_context {
>>>         struct hdmi_resources           res;
>>>
>>>         int                             hpd_gpio;
>>> +       struct regmap                   *pmureg;
>>>
>>>         enum hdmi_type                  type;
>>>   };
>>> @@ -1853,6 +1856,9 @@ static void hdmi_poweron(struct exynos_drm_display
>>> *display)
>>>         if (regulator_bulk_enable(res->regul_count, res->regul_bulk))
>>>                 DRM_DEBUG_KMS("failed to enable regulator bulk\n");
>>>
>>> +       /* set pmu hdmiphy control bit to enable hdmiphy */
>>> +       regmap_update_bits(hdata->pmureg, PMU_HDMI_PHY_CONTROL,
>>> +                       PMU_HDMI_PHY_ENABLE_BIT, 1);
>>>         clk_prepare_enable(res->hdmi);
>>>         clk_prepare_enable(res->sclk_hdmi);
>>>
>>> @@ -1879,6 +1885,10 @@ static void hdmi_poweroff(struct exynos_drm_display
>>> *display)
>>>
>>>         clk_disable_unprepare(res->sclk_hdmi);
>>>         clk_disable_unprepare(res->hdmi);
>>
>>
>> nit: Blank line would beautify the code a bit.
>>
>>> +       /* reset pmu hdmiphy control bit to disable hdmiphy */
>>> +       regmap_update_bits(hdata->pmureg, PMU_HDMI_PHY_CONTROL,
>>> +                       PMU_HDMI_PHY_ENABLE_BIT, 0);
>>> +
>>>         regulator_bulk_disable(res->regul_count, res->regul_bulk);
>>>
>>>         pm_runtime_put_sync(hdata->dev);
>>> @@ -2128,6 +2138,13 @@ static int hdmi_probe(struct platform_device *pdev)
>>>                 goto err_hdmiphy;
>>>         }
>>>
>>> +       hdata->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
>>> +                       "samsung,syscon-phandle");
>>> +       if (IS_ERR_OR_NULL(hdata->pmureg)) {
>>
>>
>> IS_ERR() is the correct macro to check return value of this function.
>>
>>> +               DRM_ERROR("syscon regmap lookup failed.\n");
>>> +               goto err_hdmiphy;
>>> +       }
>>> +
>>>         pm_runtime_enable(dev);
>>>
>>>         hdmi_display.ctx = hdata;
>>> diff --git a/drivers/gpu/drm/exynos/regs-hdmi.h
>>> b/drivers/gpu/drm/exynos/regs-hdmi.h
>>> index ef1b3eb..9811d6f 100644
>>> --- a/drivers/gpu/drm/exynos/regs-hdmi.h
>>> +++ b/drivers/gpu/drm/exynos/regs-hdmi.h
>>> @@ -578,4 +578,8 @@
>>>   #define HDMI_TG_VACT_ST4_H            HDMI_TG_BASE(0x0074)
>>>   #define HDMI_TG_3D                    HDMI_TG_BASE(0x00F0)
>>>
>>> +/* PMU Registers for PHY */
>>> +#define PMU_HDMI_PHY_CONTROL           0x700
>>> +#define PMU_HDMI_PHY_ENABLE_BIT        (1<<0)
>>
>>
>> BIT() macro could be used instead of open coding the shift.
>>
>> Best regards,
>> Tomasz