drm/bridge: samsung-dsim: add ability to define clock names for every variant

Presently, all devices refer to clock names from a single array. The
only controlling parameter is the number of clocks (num_clks field of
samsung_dsim_driver_data) which uses the first n clocks of that array.
As new devices are added, this approach turns out to be cumbersome.

Separate the clock names in individual arrays required by each variant,
in a struct clk_bulk_data. Add a pointer field to the driver data struct
which points to their respective clock names, and rework the clock usage
code to use the clk_bulk_* API instead.

Signed-off-by: Kaustabh Chakraborty <[email protected]>
Signed-off-by: Inki Dae <[email protected]>

Author: Kaustabh Chakraborty

drivers/gpu/drm/bridge/samsung-dsim.c

@@ -219,23 +219,31 @@
 #define DSI_XFER_TIMEOUT_MS		100
 #define DSI_RX_FIFO_EMPTY		0x30800002
 
-#define OLD_SCLK_MIPI_CLK_NAME		"pll_clk"
-
 #define PS_TO_CYCLE(ps, hz) DIV64_U64_ROUND_CLOSEST(((ps) * (hz)), 1000000000000ULL)
 
-static const char *const clk_names[5] = {
-	"bus_clk",
-	"sclk_mipi",
-	"phyclk_mipidphy0_bitclkdiv8",
-	"phyclk_mipidphy0_rxclkesc0",
-	"sclk_rgb_vclk_to_dsim0"
-};
-
 enum samsung_dsim_transfer_type {
 	EXYNOS_DSI_TX,
 	EXYNOS_DSI_RX,
 };
 
+static struct clk_bulk_data exynos3_clk_bulk_data[] = {
+	{ .id = "bus_clk" },
+	{ .id = "pll_clk" },
+};
+
+static struct clk_bulk_data exynos4_clk_bulk_data[] = {
+	{ .id = "bus_clk" },
+	{ .id = "sclk_mipi" },
+};
+
+static struct clk_bulk_data exynos5433_clk_bulk_data[] = {
+	{ .id = "bus_clk" },
+	{ .id = "sclk_mipi" },
+	{ .id = "phyclk_mipidphy0_bitclkdiv8" },
+	{ .id = "phyclk_mipidphy0_rxclkesc0" },
+	{ .id = "sclk_rgb_vclk_to_dsim0" },
+};
+
 enum reg_idx {
 	DSIM_STATUS_REG,	/* Status register (legacy) */
 	DSIM_LINK_STATUS_REG,	/* Link status register */
@@ -408,7 +416,8 @@ static const struct samsung_dsim_driver_data exynos3_dsi_driver_data = {
 	.has_legacy_status_reg = 1,
 	.has_freqband = 1,
 	.has_clklane_stop = 1,
-	.num_clks = 2,
+	.clk_data = exynos3_clk_bulk_data,
+	.num_clks = ARRAY_SIZE(exynos3_clk_bulk_data),
 	.max_freq = 1000,
 	.wait_for_hdr_fifo = 1,
 	.wait_for_reset = 1,
@@ -439,7 +448,8 @@ static const struct samsung_dsim_driver_data exynos4_dsi_driver_data = {
 	.has_legacy_status_reg = 1,
 	.has_freqband = 1,
 	.has_clklane_stop = 1,
-	.num_clks = 2,
+	.clk_data = exynos4_clk_bulk_data,
+	.num_clks = ARRAY_SIZE(exynos4_clk_bulk_data),
 	.max_freq = 1000,
 	.wait_for_hdr_fifo = 1,
 	.wait_for_reset = 1,
@@ -468,7 +478,8 @@ static const struct samsung_dsim_driver_data exynos5_dsi_driver_data = {
 	.reg_ofs = exynos_reg_ofs,
 	.plltmr_reg = 0x58,
 	.has_legacy_status_reg = 1,
-	.num_clks = 2,
+	.clk_data = exynos3_clk_bulk_data,
+	.num_clks = ARRAY_SIZE(exynos3_clk_bulk_data),
 	.max_freq = 1000,
 	.wait_for_hdr_fifo = 1,
 	.wait_for_reset = 1,
@@ -497,7 +508,8 @@ static const struct samsung_dsim_driver_data exynos5433_dsi_driver_data = {
 	.plltmr_reg = 0xa0,
 	.has_legacy_status_reg = 1,
 	.has_clklane_stop = 1,
-	.num_clks = 5,
+	.clk_data = exynos5433_clk_bulk_data,
+	.num_clks = ARRAY_SIZE(exynos5433_clk_bulk_data),
 	.max_freq = 1500,
 	.wait_for_hdr_fifo = 1,
 	.wait_for_reset = 0,
@@ -526,7 +538,8 @@ static const struct samsung_dsim_driver_data exynos5422_dsi_driver_data = {
 	.plltmr_reg = 0xa0,
 	.has_legacy_status_reg = 1,
 	.has_clklane_stop = 1,
-	.num_clks = 2,
+	.clk_data = exynos3_clk_bulk_data,
+	.num_clks = ARRAY_SIZE(exynos3_clk_bulk_data),
 	.max_freq = 1500,
 	.wait_for_hdr_fifo = 1,
 	.wait_for_reset = 1,
@@ -555,7 +568,8 @@ static const struct samsung_dsim_driver_data imx8mm_dsi_driver_data = {
 	.plltmr_reg = 0xa0,
 	.has_legacy_status_reg = 1,
 	.has_clklane_stop = 1,
-	.num_clks = 2,
+	.clk_data = exynos4_clk_bulk_data,
+	.num_clks = ARRAY_SIZE(exynos4_clk_bulk_data),
 	.max_freq = 2100,
 	.wait_for_hdr_fifo = 1,
 	.wait_for_reset = 0,
@@ -2021,7 +2035,7 @@ int samsung_dsim_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct samsung_dsim *dsi;
-	int ret, i;
+	int ret;
 
 	dsi = devm_drm_bridge_alloc(dev, struct samsung_dsim, bridge, &samsung_dsim_bridge_funcs);
 	if (IS_ERR(dsi))
@@ -2045,23 +2059,11 @@ int samsung_dsim_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to get regulators\n");
 
-	dsi->clks = devm_kcalloc(dev, dsi->driver_data->num_clks,
-				 sizeof(*dsi->clks), GFP_KERNEL);
-	if (!dsi->clks)
-		return -ENOMEM;
-
-	for (i = 0; i < dsi->driver_data->num_clks; i++) {
-		dsi->clks[i] = devm_clk_get(dev, clk_names[i]);
-		if (IS_ERR(dsi->clks[i])) {
-			if (strcmp(clk_names[i], "sclk_mipi") == 0) {
-				dsi->clks[i] = devm_clk_get(dev, OLD_SCLK_MIPI_CLK_NAME);
-				if (!IS_ERR(dsi->clks[i]))
-					continue;
-			}
-
-			dev_info(dev, "failed to get the clock: %s\n", clk_names[i]);
-			return PTR_ERR(dsi->clks[i]);
-		}
+	ret = devm_clk_bulk_get(dev, dsi->driver_data->num_clks,
+				dsi->driver_data->clk_data);
+	if (ret) {
+		dev_err(dev, "failed to get clocks in bulk (%d)\n", ret);
+		return ret;
 	}
 
 	dsi->reg_base = devm_platform_ioremap_resource(pdev, 0);
@@ -2134,7 +2136,7 @@ static int samsung_dsim_suspend(struct device *dev)
 {
 	struct samsung_dsim *dsi = dev_get_drvdata(dev);
 	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
-	int ret, i;
+	int ret;
 
 	usleep_range(10000, 20000);
 
@@ -2150,8 +2152,7 @@ static int samsung_dsim_suspend(struct device *dev)
 
 	phy_power_off(dsi->phy);
 
-	for (i = driver_data->num_clks - 1; i > -1; i--)
-		clk_disable_unprepare(dsi->clks[i]);
+	clk_bulk_disable_unprepare(driver_data->num_clks, driver_data->clk_data);
 
 	ret = regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
 	if (ret < 0)
@@ -2164,19 +2165,17 @@ static int samsung_dsim_resume(struct device *dev)
 {
 	struct samsung_dsim *dsi = dev_get_drvdata(dev);
 	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
-	int ret, i;
+	int ret;
 
 	ret = regulator_bulk_enable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
 	if (ret < 0) {
 		dev_err(dsi->dev, "cannot enable regulators %d\n", ret);
 		return ret;
 	}
 
-	for (i = 0; i < driver_data->num_clks; i++) {
-		ret = clk_prepare_enable(dsi->clks[i]);
-		if (ret < 0)
-			goto err_clk;
-	}
+	ret = clk_bulk_prepare_enable(driver_data->num_clks, driver_data->clk_data);
+	if (ret < 0)
+		goto err_clk;
 
 	ret = phy_power_on(dsi->phy);
 	if (ret < 0) {
@@ -2187,8 +2186,7 @@ static int samsung_dsim_resume(struct device *dev)
 	return 0;
 
 err_clk:
-	while (--i > -1)
-		clk_disable_unprepare(dsi->clks[i]);
+	clk_bulk_disable_unprepare(driver_data->num_clks, driver_data->clk_data);
 	regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
 
 	return ret;

include/drm/bridge/samsung-dsim.h

@@ -58,6 +58,7 @@ struct samsung_dsim_driver_data {
 	unsigned int has_clklane_stop:1;
 	unsigned int has_broken_fifoctrl_emptyhdr:1;
 	unsigned int has_sfrctrl:1;
+	struct clk_bulk_data *clk_data;
 	unsigned int num_clks;
 	unsigned int min_freq;
 	unsigned int max_freq;
@@ -104,7 +105,6 @@ struct samsung_dsim {
 
 	void __iomem *reg_base;
 	struct phy *phy;
-	struct clk **clks;
 	struct clk *pll_clk;
 	struct regulator_bulk_data supplies[2];
 	int irq;