[PATCH 1/4] arm64: amlogic: mmc: meson-gx: Add core, tx, rx eMMC/SD/SDIO phase clock settings from devicetree data

[Vyacheslav Bocharov]

The mmc driver has the same phase values for all meson platforms. However,
some platforms (and even some boards) require different values. This patch
transfers the values from the set in the code to the variables in the
device-tree file.

Signed-off-by: Vyacheslav Bocharov <adeep at lexina.in>

diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index df05e60bed9a..c0f32054e472 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -27,6 +27,7 @@
 #include <linux/interrupt.h>
 #include <linux/bitfield.h>
 #include <linux/pinctrl/consumer.h>
+#include <dt-bindings/mmc/meson-gx-mmc.h>
 
 #define DRIVER_NAME "meson-gx-mmc"
 
@@ -36,8 +37,6 @@
 #define   CLK_CORE_PHASE_MASK GENMASK(9, 8)
 #define   CLK_TX_PHASE_MASK GENMASK(11, 10)
 #define   CLK_RX_PHASE_MASK GENMASK(13, 12)
-#define   CLK_PHASE_0 0
-#define   CLK_PHASE_180 2
 #define   CLK_V2_TX_DELAY_MASK GENMASK(19, 16)
 #define   CLK_V2_RX_DELAY_MASK GENMASK(23, 20)
 #define   CLK_V2_ALWAYS_ON BIT(24)
@@ -428,13 +427,22 @@ static int meson_mmc_clk_init(struct meson_host *host)
 	const char *mux_parent_names[MUX_CLK_NUM_PARENTS];
 	const char *clk_parent[1];
 	u32 clk_reg;
+	u32 phase[3]; // <core_phase, tx_phase, rx_phase>
+
+	if (!(host->dev && host->dev->of_node) || (device_property_read_u32_array(host->dev,
+	    "amlogic,mmc-phase", phase, 3) < 0)) {
+		dev_dbg(host->dev, "get amlogic,mmc-phase failed, use default phase settings\n");
+		phase[0] = CLK_PHASE_180;
+		phase[1] = CLK_PHASE_0;
+		phase[2] = CLK_PHASE_0;
+	}
 
 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
 	clk_reg = CLK_ALWAYS_ON(host);
 	clk_reg |= CLK_DIV_MASK;
-	clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, CLK_PHASE_180);
-	clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, CLK_PHASE_0);
-	clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, CLK_PHASE_0);
+	clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, phase[0]);
+	clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, phase[1]);
+	clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, phase[2]);
 	clk_reg |= CLK_IRQ_SDIO_SLEEP(host);
 	writel(clk_reg, host->regs + SD_EMMC_CLOCK);
 
-- 
2.30.2