From 8b5c2b45b8f0a11c9072da0f7baf9ee986d3151e Mon Sep 17 00:00:00 2001 From: Chris Ruehl Date: Sun, 29 Nov 2020 13:44:14 +0800 Subject: [PATCH] phy: rockchip: set pulldown for strobe line in dts This patch add support to set the internal pulldown via dt property and allow simplify the board design for the trace from emmc-phy to the eMMC chipset. Default to not set the pull-down. This patch was inspired from the 4.4 tree of the Rockchip SDK, where it is enabled unconditional. The patch had been tested with our rk3399 customized board. Signed-off-by: Chris Ruehl Link: https://lore.kernel.org/r/20201129054416.3980-2-chris.ruehl@gtsys.com.hk Signed-off-by: Vinod Koul --- drivers/phy/rockchip/phy-rockchip-emmc.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c b/drivers/phy/rockchip/phy-rockchip-emmc.c index 2dc19ddd120f5a..48e2d75b100492 100644 --- a/drivers/phy/rockchip/phy-rockchip-emmc.c +++ b/drivers/phy/rockchip/phy-rockchip-emmc.c @@ -67,6 +67,10 @@ #define PHYCTRL_OTAPDLYENA_SHIFT 0xb #define PHYCTRL_OTAPDLYSEL_MASK 0xf #define PHYCTRL_OTAPDLYSEL_SHIFT 0x7 +#define PHYCTRL_REN_STRB_DISABLE 0x0 +#define PHYCTRL_REN_STRB_ENABLE 0x1 +#define PHYCTRL_REN_STRB_MASK 0x1 +#define PHYCTRL_REN_STRB_SHIFT 0x9 #define PHYCTRL_IS_CALDONE(x) \ ((((x) >> PHYCTRL_CALDONE_SHIFT) & \ @@ -80,6 +84,7 @@ struct rockchip_emmc_phy { struct regmap *reg_base; struct clk *emmcclk; unsigned int drive_impedance; + unsigned int enable_strobe_pulldown; }; static int rockchip_emmc_phy_power(struct phy *phy, bool on_off) @@ -295,6 +300,13 @@ static int rockchip_emmc_phy_power_on(struct phy *phy) PHYCTRL_OTAPDLYSEL_MASK, PHYCTRL_OTAPDLYSEL_SHIFT)); + /* Internal pull-down for strobe line */ + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON2, + HIWORD_UPDATE(rk_phy->enable_strobe_pulldown, + PHYCTRL_REN_STRB_MASK, + PHYCTRL_REN_STRB_SHIFT)); + /* Power up emmc phy analog blocks */ return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON); } @@ -359,10 +371,14 @@ static int rockchip_emmc_phy_probe(struct platform_device *pdev) rk_phy->reg_offset = reg_offset; rk_phy->reg_base = grf; rk_phy->drive_impedance = PHYCTRL_DR_50OHM; + rk_phy->enable_strobe_pulldown = PHYCTRL_REN_STRB_DISABLE; if (!of_property_read_u32(dev->of_node, "drive-impedance-ohm", &val)) rk_phy->drive_impedance = convert_drive_impedance_ohm(pdev, val); + if (of_property_read_bool(dev->of_node, "enable-strobe-pulldown")) + rk_phy->enable_strobe_pulldown = PHYCTRL_REN_STRB_ENABLE; + generic_phy = devm_phy_create(dev, dev->of_node, &ops); if (IS_ERR(generic_phy)) { dev_err(dev, "failed to create PHY\n");