Re: [PATCH] usb: phy: tegra: make the code simple by devm_platform_ioremap_resource()

From: Dmitry Osipenko
Date: Mon Jan 27 2020 - 14:47:46 EST


27.01.2020 16:58, Dejin Zheng ÐÐÑÐÑ:
> make the code simple by use devm_platform_ioremap_resource() function
> to replace platform_get_resource() and devm_ioremap().
>
> Signed-off-by: Dejin Zheng <zhengdejin5@xxxxxxxxx>
> ---
> drivers/usb/phy/phy-tegra-usb.c | 20 ++------------------
> 1 file changed, 2 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/usb/phy/phy-tegra-usb.c b/drivers/usb/phy/phy-tegra-usb.c
> index ea7ef1dc0b42..8220bb4ce1ed 100644
> --- a/drivers/usb/phy/phy-tegra-usb.c
> +++ b/drivers/usb/phy/phy-tegra-usb.c
> @@ -944,20 +944,12 @@ static int read_utmi_param(struct platform_device *pdev, const char *param,
> static int utmi_phy_probe(struct tegra_usb_phy *tegra_phy,
> struct platform_device *pdev)
> {
> - struct resource *res;
> int err;
> struct tegra_utmip_config *config;
>
> tegra_phy->is_ulpi_phy = false;
>
> - res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> - if (!res) {
> - dev_err(&pdev->dev, "Failed to get UTMI pad regs\n");
> - return -ENXIO;
> - }
> -
> - tegra_phy->pad_regs = devm_ioremap(&pdev->dev, res->start,
> - resource_size(res));
> + tegra_phy->pad_regs = devm_platform_ioremap_resource(pdev, 1);
> if (!tegra_phy->pad_regs) {
> dev_err(&pdev->dev, "Failed to remap UTMI pad regs\n");
> return -ENOMEM;
> @@ -1054,7 +1046,6 @@ MODULE_DEVICE_TABLE(of, tegra_usb_phy_id_table);
> static int tegra_usb_phy_probe(struct platform_device *pdev)
> {
> const struct of_device_id *match;
> - struct resource *res;
> struct tegra_usb_phy *tegra_phy = NULL;
> struct device_node *np = pdev->dev.of_node;
> enum usb_phy_interface phy_type;
> @@ -1071,14 +1062,7 @@ static int tegra_usb_phy_probe(struct platform_device *pdev)
> }
> tegra_phy->soc_config = match->data;
>
> - res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - if (!res) {
> - dev_err(&pdev->dev, "Failed to get I/O memory\n");
> - return -ENXIO;
> - }
> -
> - tegra_phy->regs = devm_ioremap(&pdev->dev, res->start,
> - resource_size(res));
> + tegra_phy->regs = devm_platform_ioremap_resource(pdev, 0);
> if (!tegra_phy->regs) {
> dev_err(&pdev->dev, "Failed to remap I/O memory\n");
> return -ENOMEM;
>

Hello Dejin,

Unfortunately this is not a correct change because registers are shared
by both PHY and USB controllers on Tegra SoCs. The
devm_platform_ioremap_resource() can't be used here because it makes the
mapping exclusive for a single driver, while it should be shared.