[PATCH 3/9] phy: qcom: uniphy: Update UNIPHY driver to be a common driver

[Praveenkumar I]

This patch updates the UNIPHY driver to be a common driver to
accommodate all UNIPHY / Combo PHY. This driver can be used for
both USB and PCIe UNIPHY. Using phy-mul-sel from DTS MUX selection
for USB / PCIe can be acheived.

Signed-off-by: Praveenkumar I <quic_ipkumar@xxxxxxxxxxx>
---
 drivers/phy/qualcomm/phy-qcom-uniphy.c | 401 +++++++++++++++++++++----
 1 file changed, 335 insertions(+), 66 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-uniphy.c b/drivers/phy/qualcomm/phy-qcom-uniphy.c
index da6f290af722..eb71588f5417 100644
--- a/drivers/phy/qualcomm/phy-qcom-uniphy.c
+++ b/drivers/phy/qualcomm/phy-qcom-uniphy.c
@@ -5,141 +5,410 @@
  * Based on code from
  * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
  *
+ * Modified the driver to be common for Qualcomm UNIPHYs
+ * Copyright (c) 2023, The Linux Foundation. All rights reserved.
  */
 
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 #include <linux/reset.h>
 
-struct ipq4019_usb_phy {
+struct uniphy_init_tbl {
+	unsigned int offset;
+	unsigned int val;
+};
+
+#define UNIPHY_INIT_CFG(o, v)		\
+	{				\
+		.offset = o,		\
+		.val = v,		\
+	}
+
+struct uniphy_cfg {
+	const struct uniphy_init_tbl *init_seq;
+	int num_init_seq;
+	const char * const *clk_list;
+	int num_clks;
+	const char * const *reset_list;
+	int num_resets;
+	const char * const *vreg_list;
+	int num_vregs;
+	unsigned int pipe_clk_rate;
+	unsigned int reset_udelay;
+	unsigned int autoload_udelay;
+};
+
+struct qcom_uniphy {
 	struct device		*dev;
+	const struct uniphy_cfg	*cfg;
 	struct phy		*phy;
 	void __iomem		*base;
-	struct reset_control	*por_rst;
-	struct reset_control	*srif_rst;
+	struct clk_bulk_data	*clks;
+	struct reset_control_bulk_data	*resets;
+	struct regulator_bulk_data *vregs;
+	struct clk_fixed_rate pipe_clk_fixed;
+};
+
+static const char * const ipq4019_ssphy_reset_l[] = {
+	"por_rst",
+};
+
+static const struct uniphy_cfg ipq4019_usb_ssphy_cfg = {
+	.reset_list	= ipq4019_ssphy_reset_l,
+	.num_resets	= ARRAY_SIZE(ipq4019_ssphy_reset_l),
+	.reset_udelay	= 10000,
+
 };
 
-static int ipq4019_ss_phy_power_off(struct phy *_phy)
+static const char * const ipq4019_hsphy_reset_l[] = {
+	"por_rst", "srif_rst",
+};
+
+static const struct uniphy_cfg ipq4019_usb_hsphy_cfg = {
+	.reset_list	= ipq4019_hsphy_reset_l,
+	.num_resets	= ARRAY_SIZE(ipq4019_hsphy_reset_l),
+	.reset_udelay	= 10000,
+};
+
+static int phy_mux_sel(struct phy *phy)
+{
+	struct qcom_uniphy *uniphy = phy_get_drvdata(phy);
+	struct device *dev = uniphy->dev;
+	struct regmap *tcsr;
+	unsigned int args[2];
+	int ret;
+
+	tcsr = syscon_regmap_lookup_by_phandle_args(dev->of_node, "qcom,phy-mux-sel",
+						    ARRAY_SIZE(args), args);
+	if (IS_ERR(tcsr)) {
+		ret = PTR_ERR(tcsr);
+		if (ret == -ENOENT)
+			return 0;
+
+		dev_err(dev, "failed to lookup syscon for phy mux %d\n", ret);
+		return ret;
+	}
+
+	/* PHY MUX registers only have this BIT0 */
+	ret = regmap_write(tcsr, args[0], args[1]);
+	if (ret < 0) {
+		dev_err(dev, "PHY Mux selection failed: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int uniphy_enable(struct phy *phy)
 {
-	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
+	struct qcom_uniphy *uniphy = phy_get_drvdata(phy);
+	const struct uniphy_cfg *cfg = uniphy->cfg;
+	const struct uniphy_init_tbl *tbl;
+	void __iomem *base = uniphy->base;
+	int i, ret;
 
-	reset_control_assert(phy->por_rst);
-	msleep(10);
+	ret = regulator_bulk_enable(cfg->num_vregs, uniphy->vregs);
+	if (ret) {
+		dev_err(uniphy->dev, "failed to enable regulators: %d\n", ret);
+		return ret;
+	}
+
+	/* Assert all available resets */
+	for (i = 0; i < cfg->num_resets; i++) {
+		ret = reset_control_assert(uniphy->resets[i].rstc);
+		if (ret) {
+			dev_err(uniphy->dev, "reset assert failed: %d\n", ret);
+			goto err_assert_reset;
+		}
+		if (cfg->reset_udelay)
+			usleep_range(cfg->reset_udelay, cfg->reset_udelay + 10);
+	}
+
+	/* Deassert all available resets */
+	for (i = 0; i < cfg->num_resets; i++) {
+		ret = reset_control_deassert(uniphy->resets[i].rstc);
+		if (ret) {
+			dev_err(uniphy->dev, "reset deassert failed: %d\n", ret);
+			goto err_assert_reset;
+		}
+		if (cfg->reset_udelay)
+			usleep_range(cfg->reset_udelay, cfg->reset_udelay + 10);
+	}
+
+	ret = phy_mux_sel(phy);
+	if (ret < 0)
+		goto err_assert_reset;
+
+	ret = clk_bulk_prepare_enable(cfg->num_clks, uniphy->clks);
+	if (ret) {
+		dev_err(uniphy->dev, "failed to enable clocks: %d\n", ret);
+		goto err_assert_reset;
+	}
+
+	if (cfg->autoload_udelay)
+		usleep_range(cfg->autoload_udelay, cfg->autoload_udelay + 10);
+
+	if (cfg->num_init_seq) {
+		tbl = cfg->init_seq;
+		for (i = 0; i < cfg->num_init_seq; i++, tbl++)
+			writel(tbl->val, base + tbl->offset);
+	}
 
 	return 0;
+
+err_assert_reset:
+	/* Assert all available resets */
+	for (i = 0; i < cfg->num_resets; i++) {
+		reset_control_assert(uniphy->resets[i].rstc);
+		if (cfg->reset_udelay)
+			usleep_range(cfg->reset_udelay, cfg->reset_udelay + 10);
+	}
+
+	return ret;
 }
 
-static int ipq4019_ss_phy_power_on(struct phy *_phy)
+static int uniphy_disable(struct phy *phy)
 {
-	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
+	struct qcom_uniphy *uniphy = phy_get_drvdata(phy);
+	const struct uniphy_cfg *cfg = uniphy->cfg;
+	int i;
 
-	ipq4019_ss_phy_power_off(_phy);
+	/* Assert all available resets */
+	for (i = 0; i < cfg->num_resets; i++) {
+		reset_control_assert(uniphy->resets[i].rstc);
+		if (cfg->reset_udelay)
+			usleep_range(cfg->reset_udelay, cfg->reset_udelay + 10);
+	}
 
-	reset_control_deassert(phy->por_rst);
+	clk_bulk_disable_unprepare(cfg->num_clks, uniphy->clks);
+
+	regulator_bulk_disable(cfg->num_vregs, uniphy->vregs);
 
 	return 0;
 }
 
-static const struct phy_ops ipq4019_usb_ss_phy_ops = {
-	.power_on	= ipq4019_ss_phy_power_on,
-	.power_off	= ipq4019_ss_phy_power_off,
+static const struct phy_ops uniphy_phy_ops = {
+	.power_on	= uniphy_enable,
+	.power_off	= uniphy_disable,
+	.owner		= THIS_MODULE,
 };
 
-static int ipq4019_hs_phy_power_off(struct phy *_phy)
+static int qcom_uniphy_vreg_init(struct qcom_uniphy *uniphy)
+{
+	const struct uniphy_cfg *cfg = uniphy->cfg;
+	struct device *dev = uniphy->dev;
+	int i, ret;
+
+	uniphy->vregs = devm_kcalloc(dev, cfg->num_vregs,
+				     sizeof(*uniphy->vregs), GFP_KERNEL);
+	if (!uniphy->vregs)
+		return -ENOMEM;
+
+	for (i = 0; i < cfg->num_vregs; i++)
+		uniphy->vregs[i].supply = cfg->vreg_list[i];
+
+	ret = devm_regulator_bulk_get(dev, cfg->num_vregs, uniphy->vregs);
+
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to get regulators\n");
+
+	return 0;
+}
+
+static int qcom_uniphy_reset_init(struct qcom_uniphy *uniphy)
 {
-	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
+	const struct uniphy_cfg *cfg = uniphy->cfg;
+	struct device *dev = uniphy->dev;
+	int i, ret;
+
+	uniphy->resets = devm_kcalloc(dev, cfg->num_resets,
+				      sizeof(*uniphy->resets), GFP_KERNEL);
+	if (!uniphy->resets)
+		return -ENOMEM;
 
-	reset_control_assert(phy->por_rst);
-	msleep(10);
+	for (i = 0; i < cfg->num_resets; i++)
+		uniphy->resets[i].id = cfg->reset_list[i];
 
-	reset_control_assert(phy->srif_rst);
-	msleep(10);
+	ret = devm_reset_control_bulk_get_exclusive(dev, cfg->num_resets, uniphy->resets);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to get resets\n");
 
 	return 0;
 }
 
-static int ipq4019_hs_phy_power_on(struct phy *_phy)
+static int qcom_uniphy_clk_init(struct qcom_uniphy *uniphy)
 {
-	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
+	const struct uniphy_cfg *cfg = uniphy->cfg;
+	struct device *dev = uniphy->dev;
+	int i, ret;
 
-	ipq4019_hs_phy_power_off(_phy);
 
-	reset_control_deassert(phy->srif_rst);
-	msleep(10);
+	uniphy->clks = devm_kcalloc(dev, cfg->num_clks,
+				    sizeof(*uniphy->clks), GFP_KERNEL);
+	if (!uniphy->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < cfg->num_clks; i++)
+		uniphy->clks[i].id = cfg->clk_list[i];
 
-	reset_control_deassert(phy->por_rst);
+	ret = devm_clk_bulk_get(dev, cfg->num_clks, uniphy->clks);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to get clocks\n");
 
 	return 0;
 }
 
-static const struct phy_ops ipq4019_usb_hs_phy_ops = {
-	.power_on	= ipq4019_hs_phy_power_on,
-	.power_off	= ipq4019_hs_phy_power_off,
-};
+static void phy_clk_release_provider(void *res)
+{
+	of_clk_del_provider(res);
+}
 
-static const struct of_device_id ipq4019_usb_phy_of_match[] = {
-	{ .compatible = "qcom,usb-hs-ipq4019-phy", .data = &ipq4019_usb_hs_phy_ops},
-	{ .compatible = "qcom,usb-ss-ipq4019-phy", .data = &ipq4019_usb_ss_phy_ops},
-	{ },
-};
-MODULE_DEVICE_TABLE(of, ipq4019_usb_phy_of_match);
+/*
+ * Register a fixed rate pipe clock.
+ *
+ * The <s>_pipe_clksrc generated by PHY goes to the GCC that gate
+ * controls it. The <s>_pipe_clk coming out of the GCC is requested
+ * by the PHY driver for its operations.
+ * We register the <s>_pipe_clksrc here. The gcc driver takes care
+ * of assigning this <s>_pipe_clksrc as parent to <s>_pipe_clk.
+ * Below picture shows this relationship.
+ *
+ *         +---------------+
+ *         |   PHY block   |<<---------------------------------------+
+ *         |               |                                         |
+ *         |   +-------+   |                   +-----+               |
+ *   I/P---^-->|  PLL  |---^--->pipe_clksrc--->| GCC |--->pipe_clk---+
+ *    clk  |   +-------+   |                   +-----+
+ *         +---------------+
+ */
+static int phy_pipe_clk_register(struct qcom_uniphy *uniphy, struct device_node *np)
+{
+	struct clk_fixed_rate *fixed = &uniphy->pipe_clk_fixed;
+	const struct uniphy_cfg *cfg = uniphy->cfg;
+	struct device *dev = uniphy->dev;
+	struct clk_init_data init = { };
+	int ret;
+
+	ret = of_property_read_string(np, "clock-output-names", &init.name);
+	if (ret) {
+		dev_err(dev, "%pOFn: No clock-output-names\n", np);
+		return ret;
+	}
+
+	init.ops = &clk_fixed_rate_ops;
+
+	fixed->fixed_rate = cfg->pipe_clk_rate;
+	fixed->hw.init = &init;
 
-static int ipq4019_usb_phy_probe(struct platform_device *pdev)
+	ret = devm_clk_hw_register(dev, &fixed->hw);
+	if (ret)
+		return ret;
+
+	ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &fixed->hw);
+	if (ret)
+		return ret;
+
+	/*
+	 * Roll a devm action because the clock provider is the child node, but
+	 * the child node is not actually a device.
+	 */
+	return devm_add_action_or_reset(dev, phy_clk_release_provider, np);
+}
+
+static int qcom_uniphy_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct phy_provider *phy_provider;
-	struct ipq4019_usb_phy *phy;
+	struct qcom_uniphy *uniphy;
+	struct device_node *np;
+	int ret;
 
-	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
-	if (!phy)
+	uniphy = devm_kzalloc(dev, sizeof(*uniphy), GFP_KERNEL);
+	if (!uniphy)
 		return -ENOMEM;
 
-	phy->dev = &pdev->dev;
-	phy->base = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(phy->base)) {
-		dev_err(dev, "failed to remap register memory\n");
-		return PTR_ERR(phy->base);
-	}
+	uniphy->dev = dev;
 
-	phy->por_rst = devm_reset_control_get(phy->dev, "por_rst");
-	if (IS_ERR(phy->por_rst)) {
-		if (PTR_ERR(phy->por_rst) != -EPROBE_DEFER)
-			dev_err(dev, "POR reset is missing\n");
-		return PTR_ERR(phy->por_rst);
+	uniphy->cfg = of_device_get_match_data(dev);
+	if (!uniphy->cfg)
+		return -EINVAL;
+
+	uniphy->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(uniphy->base)) {
+		ret = PTR_ERR(uniphy->base);
+		dev_err_probe(dev, ret, "failed to remap register memory\n");
+		return ret;
 	}
 
-	phy->srif_rst = devm_reset_control_get_optional(phy->dev, "srif_rst");
-	if (IS_ERR(phy->srif_rst))
-		return PTR_ERR(phy->srif_rst);
+	ret = qcom_uniphy_clk_init(uniphy);
+	if (ret)
+		return ret;
+
+	ret = qcom_uniphy_reset_init(uniphy);
+	if (ret)
+		return ret;
+
+	ret = qcom_uniphy_vreg_init(uniphy);
+	if (ret < 0)
+		return ret;
+
+	if (uniphy->cfg->pipe_clk_rate) {
+		np = of_node_get(dev->of_node);
+		ret = phy_pipe_clk_register(uniphy, np);
+		if (ret) {
+			dev_err_probe(dev, ret, "failed to register pipe clk\n");
+			goto err;
+		}
+	}
 
-	phy->phy = devm_phy_create(dev, NULL, of_device_get_match_data(dev));
-	if (IS_ERR(phy->phy)) {
-		dev_err(dev, "failed to create PHY\n");
-		return PTR_ERR(phy->phy);
+	uniphy->phy = devm_phy_create(dev, NULL, &uniphy_phy_ops);
+	if (IS_ERR(uniphy->phy)) {
+		ret = PTR_ERR(uniphy->phy);
+		dev_err_probe(dev, ret, "failed to create PHY\n");
+		goto err;
 	}
-	phy_set_drvdata(phy->phy, phy);
+
+	phy_set_drvdata(uniphy->phy, uniphy);
 
 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 
-	return PTR_ERR_OR_ZERO(phy_provider);
+	ret = PTR_ERR_OR_ZERO(phy_provider);
+
+err:
+	if (uniphy->cfg->pipe_clk_rate)
+		of_node_put(np);
+	return ret;
 }
 
-static struct platform_driver ipq4019_usb_phy_driver = {
-	.probe	= ipq4019_usb_phy_probe,
+static const struct of_device_id qcom_uniphy_of_match[] = {
+	{ .compatible = "qcom,usb-hs-ipq4019-phy", .data = &ipq4019_usb_hsphy_cfg},
+	{ .compatible = "qcom,usb-ss-ipq4019-phy", .data = &ipq4019_usb_ssphy_cfg},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, qcom_uniphy_of_match);
+
+static struct platform_driver qcom_uniphy_driver = {
+	.probe	= qcom_uniphy_probe,
 	.driver = {
-		.of_match_table	= ipq4019_usb_phy_of_match,
-		.name  = "ipq4019-usb-phy",
+		.of_match_table	= qcom_uniphy_of_match,
+		.name  = "qcom-uniphy",
 	}
 };
-module_platform_driver(ipq4019_usb_phy_driver);
+module_platform_driver(qcom_uniphy_driver);
 
-MODULE_DESCRIPTION("QCOM/IPQ4019 USB phy driver");
+MODULE_DESCRIPTION("QCOM uniphy driver");
 MODULE_AUTHOR("John Crispin <john@xxxxxxxxxxx>");
 MODULE_LICENSE("GPL v2");
-- 
2.34.1