Re: [PATCH v2 1/4] drm/rockchip/dsi: check phy_cfg_clk only for RK3399

From: John Keeping
Date: Thu Mar 16 2017 - 06:55:59 EST


On Thu, 16 Mar 2017 11:31:44 +0800, Chris Zhong wrote:

> For RK3399, the phy_cfg_clk is a required clock, if phy_cfg_clk is
> disabled, MIPI phy can not work. Let's return a error if there is no
> phy_cfg_clk in dts property, when the pdata match RK3399.
>
> Signed-off-by: Chris Zhong <zyw@xxxxxxxxxxxxxx>
> ---
>
> Changes in v2: None
>
> drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> index f84f9ae..11c4166 100644
> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> @@ -1227,15 +1227,13 @@ static int dw_mipi_dsi_bind(struct device *dev, struct device *master,
> clk_disable_unprepare(dsi->pclk);
> }
>
> - dsi->phy_cfg_clk = devm_clk_get(dev, "phy_cfg");
> - if (IS_ERR(dsi->phy_cfg_clk)) {
> - ret = PTR_ERR(dsi->phy_cfg_clk);
> - if (ret != -ENOENT) {
> + if (pdata == &rk3399_mipi_dsi_drv_data) {

This will get messy if the next SOC also needs phy_cfg_clk. Can we do
something like:

if (pdata->flags & DW_MIPI_NEEDS_PHY_CFG_CLK) {
...

> + dsi->phy_cfg_clk = devm_clk_get(dev, "phy_cfg");
> + if (IS_ERR(dsi->phy_cfg_clk)) {
> + ret = PTR_ERR(dsi->phy_cfg_clk);
> dev_err(dev, "Unable to get phy_cfg_clk: %d\n", ret);
> return ret;
> }
> - dsi->phy_cfg_clk = NULL;
> - dev_dbg(dev, "have not phy_cfg_clk\n");
> }
>
> ret = clk_prepare_enable(dsi->pllref_clk);