[PATCH V5 1/2] video: exynos_dp: Add device tree support to DP driver
Sylwester Nawrocki
sylvester.nawrocki at gmail.com
Sat Oct 13 08:44:05 EST 2012
On 10/12/2012 10:47 PM, Ajay Kumar wrote:
> This patch enables device tree based discovery support for DP driver.
> The driver is modified to handle platform data in both the cases:
> with DT and non-DT.
>
> Signed-off-by: Ajay Kumar<ajaykumar.rs at samsung.com>
> Acked-by: Jingoo Han<jg1.han at samsung.com>
> ---
> drivers/video/exynos/exynos_dp_core.c | 161 ++++++++++++++++++++++++++++++---
> drivers/video/exynos/exynos_dp_core.h | 2 +
> 2 files changed, 149 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/video/exynos/exynos_dp_core.c b/drivers/video/exynos/exynos_dp_core.c
> index d55470e..62932ba 100644
> --- a/drivers/video/exynos/exynos_dp_core.c
> +++ b/drivers/video/exynos/exynos_dp_core.c
> @@ -18,6 +18,7 @@
> #include<linux/io.h>
> #include<linux/interrupt.h>
> #include<linux/delay.h>
> +#include<linux/of.h>
>
> #include<video/exynos_dp.h>
>
> @@ -856,6 +857,99 @@ static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
> return IRQ_HANDLED;
> }
>
> +#ifdef CONFIG_OF
> +struct exynos_dp_platdata *exynos_dp_dt_parse_pdata(struct device *dev)
> +{
> + struct device_node *dp_node = dev->of_node;
> + struct exynos_dp_platdata *pd;
> + struct video_info *dp_video_config;
> +
> + pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
> + if (!pd) {
> + dev_err(dev, "memory allocation for pdata failed\n");
> + return ERR_PTR(-ENOMEM);
> + }
> + dp_video_config = devm_kzalloc(dev,
> + sizeof(*dp_video_config), GFP_KERNEL);
> +
> + if (!dp_video_config) {
> + dev_err(dev, "memory allocation for video config failed\n");
> + return ERR_PTR(-ENOMEM);
> + }
> + pd->video_info = dp_video_config;
> +
> + if (of_get_property(dp_node, "hsync-active-high", NULL))
> + dp_video_config->h_sync_polarity = 1;
> +
> + if (of_get_property(dp_node, "vsync-active-high", NULL))
> + dp_video_config->v_sync_polarity = 1;
> +
> + if (of_get_property(dp_node, "interlaced", NULL))
> + dp_video_config->interlaced = 1;
of_property_read_bool() could also be used here.
> +
> + of_property_read_u32(dp_node, "samsung,color-space",
> + &dp_video_config->color_space);
> +
> + of_property_read_u32(dp_node, "samsung,dynamic-range",
> + &dp_video_config->dynamic_range);
> +
> + of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
> + &dp_video_config->ycbcr_coeff);
> +
> + of_property_read_u32(dp_node, "samsung,color-depth",
> + &dp_video_config->color_depth);
> +
> + of_property_read_u32(dp_node, "samsung,link-rate",
> + &dp_video_config->link_rate);
> +
> + of_property_read_u32(dp_node, "samsung,lane-count",
> + &dp_video_config->lane_count);
Shouldn't it be checked whether all these required properties are present ?
If someone forgets to specify any one the driver will silently ignore it,
not giving a clue what's wrong.
> + return pd;
> +}
> +
> +void exynos_dp_dt_parse_phydata(struct exynos_dp_device *dp)
> +{
> + struct device_node *dp_phy_node;
> + u32 phy_base;
> + void *virt_phy_base;
> +
> + dp_phy_node = of_find_node_by_name(dp->dev->of_node, "dptx-phy");
> + if (!dp_phy_node) {
> + dp->dp_phy_addr = NULL;
Is this required ? You've allocated dp with kzalloc().
> + return;
> + }
> +
> + of_property_read_u32(dp_phy_node, "reg",&phy_base);
> + of_property_read_u32(dp_phy_node, "samsung,enable-mask",
> + &dp->enable_mask);
I think you should check the return values, these are required properties.
Some error logs might be useful here.
> + virt_phy_base = ioremap(phy_base, SZ_4);
How about assigning to dp->dp_phy_addr directly and gettting rid of
virt_phy_base ?
> + if (!virt_phy_base) {
> + dev_err(dp->dev, "failed to ioremap dp-phy\n");
> + dp->dp_phy_addr = NULL;
> + return;
> + }
> + dp->dp_phy_addr = virt_phy_base;
> +}
> +
> +void exynos_dp_phy_init(struct exynos_dp_device *dp)
> +{
> + u32 reg;
> +
> + reg = __raw_readl(dp->dp_phy_addr);
> + reg |= dp->enable_mask;
> + __raw_writel(reg, dp->dp_phy_addr);
> +}
> +
> +void exynos_dp_phy_exit(struct exynos_dp_device *dp)
> +{
> + u32 reg;
> +
> + reg = __raw_readl(dp->dp_phy_addr);
> + reg&= ~(dp->enable_mask);
> + __raw_writel(reg, dp->dp_phy_addr);
> +}
> +#endif /* CONFIG_OF */
> +
> static int __devinit exynos_dp_probe(struct platform_device *pdev)
> {
> struct resource *res;
> @@ -864,12 +958,6 @@ static int __devinit exynos_dp_probe(struct platform_device *pdev)
>
> int ret = 0;
>
> - pdata = pdev->dev.platform_data;
> - if (!pdata) {
> - dev_err(&pdev->dev, "no platform data\n");
> - return -EINVAL;
> - }
> -
> dp = devm_kzalloc(&pdev->dev, sizeof(struct exynos_dp_device),
> GFP_KERNEL);
> if (!dp) {
> @@ -879,6 +967,21 @@ static int __devinit exynos_dp_probe(struct platform_device *pdev)
>
> dp->dev =&pdev->dev;
>
> + if (pdev->dev.of_node) {
> + pdata = exynos_dp_dt_parse_pdata(&pdev->dev);
> + if (IS_ERR(pdata))
> + return PTR_ERR(pdata);
> +
> + exynos_dp_dt_parse_phydata(dp);
> + } else {
> + pdata = pdev->dev.platform_data;
> + }
> +
> + if (!pdata) {
> + dev_err(&pdev->dev, "no platform data\n");
> + return -EINVAL;
> + }
> +
This check is only reqired for non-dt case, might be worth to move
it under else statement above.
> dp->clock = devm_clk_get(&pdev->dev, "dp");
> if (IS_ERR(dp->clock)) {
> dev_err(&pdev->dev, "failed to get clock\n");
> @@ -909,8 +1012,14 @@ static int __devinit exynos_dp_probe(struct platform_device *pdev)
> }
>
> dp->video_info = pdata->video_info;
> - if (pdata->phy_init)
> - pdata->phy_init();
> +
> + if (pdev->dev.of_node) {
> + if (dp->dp_phy_addr)
> + exynos_dp_phy_init(dp);
> + } else {
> + if (pdata->phy_init)
> + pdata->phy_init();
> + }
>
> exynos_dp_init_dp(dp);
>
> @@ -953,8 +1062,13 @@ static int __devexit exynos_dp_remove(struct platform_device *pdev)
> struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
> struct exynos_dp_device *dp = platform_get_drvdata(pdev);
This doesn't belong to your patch, but the above 2 lines could be written as:
struct exynos_dp_device *dp = dev_get_drvdata(&pdev->dev);
Same in functions exynos_dp_suspend() and exynos_dp_resume().
>
> - if (pdata&& pdata->phy_exit)
> - pdata->phy_exit();
> + if (pdev->dev.of_node) {
> + if (dp->dp_phy_addr)
> + exynos_dp_phy_exit(dp);
> + } else {
> + if (pdata&& pdata->phy_exit)
> + pdata->phy_exit();
> + }
It is not possible to have valid dp->dp_phy_addr pointer without
valid pdev->dev.of_node, is it ?
Can't this (and all similar occurrences) be simplified to:
if (dp->dp_phy_addr)
exynos_dp_phy_exit(dp);
else if (pdata->phy_exit)
pdata->phy_exit();
?
It just requires dp->dp_phy_addr being NULL for non-dt case.
pdata is never NULL, otherwise probe() would have already failed.
> clk_disable_unprepare(dp->clock);
>
> @@ -968,8 +1082,13 @@ static int exynos_dp_suspend(struct device *dev)
> struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
> struct exynos_dp_device *dp = platform_get_drvdata(pdev);
>
> - if (pdata&& pdata->phy_exit)
> - pdata->phy_exit();
> + if (dev->of_node) {
> + if (dp->dp_phy_addr)
> + exynos_dp_phy_exit(dp);
> + } else {
> + if (pdata&& pdata->phy_exit)
> + pdata->phy_exit();
> + }
>
> clk_disable_unprepare(dp->clock);
>
> @@ -982,8 +1101,13 @@ static int exynos_dp_resume(struct device *dev)
> struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
> struct exynos_dp_device *dp = platform_get_drvdata(pdev);
>
> - if (pdata&& pdata->phy_init)
> - pdata->phy_init();
> + if (dev->of_node) {
> + if (dp->dp_phy_addr)
> + exynos_dp_phy_init(dp);
> + } else {
> + if (pdata&& pdata->phy_init)
> + pdata->phy_init();
> + }
>
> clk_prepare_enable(dp->clock);
>
> @@ -1013,6 +1137,14 @@ static const struct dev_pm_ops exynos_dp_pm_ops = {
> SET_SYSTEM_SLEEP_PM_OPS(exynos_dp_suspend, exynos_dp_resume)
> };
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id exynos_dp_match[] = {
> + { .compatible = "samsung,exynos5-dp" },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, exynos_dp_match);
> +#endif
> +
How about just dropping this #ifdef, since you're using of_match_ptr() ?
> static struct platform_driver exynos_dp_driver = {
> .probe = exynos_dp_probe,
> .remove = __devexit_p(exynos_dp_remove),
> @@ -1020,6 +1152,7 @@ static struct platform_driver exynos_dp_driver = {
> .name = "exynos-dp",
> .owner = THIS_MODULE,
> .pm =&exynos_dp_pm_ops,
> + .of_match_table = of_match_ptr(exynos_dp_match),
> },
> };
>
> diff --git a/drivers/video/exynos/exynos_dp_core.h b/drivers/video/exynos/exynos_dp_core.h
> index 57b8a65..569858b 100644
> --- a/drivers/video/exynos/exynos_dp_core.h
> +++ b/drivers/video/exynos/exynos_dp_core.h
> @@ -29,6 +29,8 @@ struct exynos_dp_device {
> struct clk *clock;
> unsigned int irq;
> void __iomem *reg_base;
> + void __iomem *dp_phy_addr;
Nit: "dp" is already within the structure name. How about just
naming it phy_addr ? dp->phy_addr might look better than
dp->dp_phy_addr ;)
> + unsigned int enable_mask;
>
> struct video_info *video_info;
> struct link_train link_train;
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