Try to get drive impedance from DT and use it, otherwise use 50ohm by default in order not to break the existing boards as 50ohm works fine for them already. Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> --- drivers/phy/phy-rockchip-emmc.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c index f1b24f1..7fd4a3e 100644 --- a/drivers/phy/phy-rockchip-emmc.c +++ b/drivers/phy/phy-rockchip-emmc.c @@ -78,6 +78,7 @@ struct rockchip_emmc_phy { unsigned int reg_offset; + unsigned int drive_impedance; struct regmap *reg_base; struct clk *emmcclk; }; @@ -288,7 +289,7 @@ static int rockchip_emmc_phy_power_on(struct phy *phy) /* Drive impedance: 50 Ohm */ regmap_write(rk_phy->reg_base, rk_phy->reg_offset + GRF_EMMCPHY_CON6, - HIWORD_UPDATE(PHYCTRL_DR_50OHM, + HIWORD_UPDATE(rk_phy->drive_impedance, PHYCTRL_DR_MASK, PHYCTRL_DR_SHIFT)); @@ -346,6 +347,32 @@ static int rockchip_emmc_phy_probe(struct platform_device *pdev) return -EINVAL; } + rk_phy->drive_impedance = PHYCTRL_DR_50OHM; + if (!of_property_read_u32(dev->of_node, "drive_impedance", + &rk_phy->drive_impedance)) { + switch (rk_phy->drive_impedance) { + case 33: + rk_phy->drive_impedance = PHYCTRL_DR_33OHM; + break; + case 40: + rk_phy->drive_impedance = PHYCTRL_DR_40OHM; + break; + case 50: + rk_phy->drive_impedance = PHYCTRL_DR_50OHM; + break; + case 66: + rk_phy->drive_impedance = PHYCTRL_DR_66OHM; + break; + case 100: + rk_phy->drive_impedance = PHYCTRL_DR_100OHM; + break; + default: + dev_info(dev, "invalid drive impedance.\n"); + rk_phy->drive_impedance = PHYCTRL_DR_50OHM; + break; + } + } + rk_phy->reg_offset = reg_offset; rk_phy->reg_base = grf; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html