phy: freescale: Add i.MX8qm Mixel LVDS PHY support
authorLiu Ying <victor.liu@nxp.com>
Wed, 6 Jul 2022 03:48:10 +0000 (11:48 +0800)
committerVinod Koul <vkoul@kernel.org>
Fri, 8 Jul 2022 05:13:20 +0000 (10:43 +0530)
Add Freescale i.MX8qm LVDS PHY support.
The PHY IP is from Mixel, Inc.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
Link: https://lore.kernel.org/r/20220706034810.2352641-4-victor.liu@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
drivers/phy/freescale/Kconfig
drivers/phy/freescale/Makefile
drivers/phy/freescale/phy-fsl-imx8qm-lvds-phy.c [new file with mode: 0644]

index f9c54cd..853958f 100644 (file)
@@ -8,6 +8,15 @@ config PHY_FSL_IMX8MQ_USB
        select GENERIC_PHY
        default ARCH_MXC && ARM64
 
+config PHY_MIXEL_LVDS_PHY
+       tristate "Mixel LVDS PHY support"
+       depends on OF
+       select GENERIC_PHY
+       select REGMAP_MMIO
+       help
+         Enable this to add support for the Mixel LVDS PHY as found
+         on NXP's i.MX8qm SoC.
+
 config PHY_MIXEL_MIPI_DPHY
        tristate "Mixel MIPI DSI PHY support"
        depends on OF && HAS_IOMEM
index 3518d5d..cedb328 100644 (file)
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_PHY_FSL_IMX8MQ_USB)       += phy-fsl-imx8mq-usb.o
+obj-$(CONFIG_PHY_MIXEL_LVDS_PHY)       += phy-fsl-imx8qm-lvds-phy.o
 obj-$(CONFIG_PHY_MIXEL_MIPI_DPHY)      += phy-fsl-imx8-mipi-dphy.o
 obj-$(CONFIG_PHY_FSL_IMX8M_PCIE)       += phy-fsl-imx8m-pcie.o
 obj-$(CONFIG_PHY_FSL_LYNX_28G)         += phy-fsl-lynx-28g.o
diff --git a/drivers/phy/freescale/phy-fsl-imx8qm-lvds-phy.c b/drivers/phy/freescale/phy-fsl-imx8qm-lvds-phy.c
new file mode 100644 (file)
index 0000000..e514b64
--- /dev/null
@@ -0,0 +1,450 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2017-2020,2022 NXP
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/units.h>
+
+#define REG_SET                0x4
+#define REG_CLR                0x8
+
+#define PHY_CTRL       0x0
+#define  M_MASK                GENMASK(18, 17)
+#define  M(n)          FIELD_PREP(M_MASK, (n))
+#define  CCM_MASK      GENMASK(16, 14)
+#define  CCM(n)                FIELD_PREP(CCM_MASK, (n))
+#define  CA_MASK       GENMASK(13, 11)
+#define  CA(n)         FIELD_PREP(CA_MASK, (n))
+#define  TST_MASK      GENMASK(10, 5)
+#define  TST(n)                FIELD_PREP(TST_MASK, (n))
+#define  CH_EN(id)     BIT(3 + (id))
+#define  NB            BIT(2)
+#define  RFB           BIT(1)
+#define  PD            BIT(0)
+
+/* Power On Reset(POR) value */
+#define  CTRL_RESET_VAL        (M(0x0) | CCM(0x4) | CA(0x4) | TST(0x25))
+
+/* PHY initialization value and mask */
+#define  CTRL_INIT_MASK        (M_MASK | CCM_MASK | CA_MASK | TST_MASK | NB | RFB)
+#define  CTRL_INIT_VAL (M(0x0) | CCM(0x5) | CA(0x4) | TST(0x25) | RFB)
+
+#define PHY_STATUS     0x10
+#define  LOCK          BIT(0)
+
+#define PHY_NUM                2
+
+#define MIN_CLKIN_FREQ (25 * MEGA)
+#define MAX_CLKIN_FREQ (165 * MEGA)
+
+#define PLL_LOCK_SLEEP         10
+#define PLL_LOCK_TIMEOUT       1000
+
+struct mixel_lvds_phy {
+       struct phy *phy;
+       struct phy_configure_opts_lvds cfg;
+       unsigned int id;
+};
+
+struct mixel_lvds_phy_priv {
+       struct regmap *regmap;
+       struct mutex lock;      /* protect remap access and cfg of our own */
+       struct clk *phy_ref_clk;
+       struct mixel_lvds_phy *phys[PHY_NUM];
+};
+
+static int mixel_lvds_phy_init(struct phy *phy)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(phy->dev.parent);
+
+       mutex_lock(&priv->lock);
+       regmap_update_bits(priv->regmap,
+                          PHY_CTRL, CTRL_INIT_MASK, CTRL_INIT_VAL);
+       mutex_unlock(&priv->lock);
+
+       return 0;
+}
+
+static int mixel_lvds_phy_power_on(struct phy *phy)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(phy->dev.parent);
+       struct mixel_lvds_phy *lvds_phy = phy_get_drvdata(phy);
+       struct mixel_lvds_phy *companion = priv->phys[lvds_phy->id ^ 1];
+       struct phy_configure_opts_lvds *cfg = &lvds_phy->cfg;
+       u32 val = 0;
+       u32 locked;
+       int ret;
+
+       /* The master PHY would power on the slave PHY. */
+       if (cfg->is_slave)
+               return 0;
+
+       ret = clk_prepare_enable(priv->phy_ref_clk);
+       if (ret < 0) {
+               dev_err(&phy->dev,
+                       "failed to enable PHY reference clock: %d\n", ret);
+               return ret;
+       }
+
+       mutex_lock(&priv->lock);
+       if (cfg->bits_per_lane_and_dclk_cycle == 7) {
+               if (cfg->differential_clk_rate < 44000000)
+                       val |= M(0x2);
+               else if (cfg->differential_clk_rate < 90000000)
+                       val |= M(0x1);
+               else
+                       val |= M(0x0);
+       } else {
+               val = NB;
+
+               if (cfg->differential_clk_rate < 32000000)
+                       val |= M(0x2);
+               else if (cfg->differential_clk_rate < 63000000)
+                       val |= M(0x1);
+               else
+                       val |= M(0x0);
+       }
+       regmap_update_bits(priv->regmap, PHY_CTRL, M_MASK | NB, val);
+
+       /*
+        * Enable two channels synchronously,
+        * if the companion PHY is a slave PHY.
+        */
+       if (companion->cfg.is_slave)
+               val = CH_EN(0) | CH_EN(1);
+       else
+               val = CH_EN(lvds_phy->id);
+       regmap_write(priv->regmap, PHY_CTRL + REG_SET, val);
+
+       ret = regmap_read_poll_timeout(priv->regmap, PHY_STATUS, locked,
+                                      locked, PLL_LOCK_SLEEP,
+                                      PLL_LOCK_TIMEOUT);
+       if (ret < 0) {
+               dev_err(&phy->dev, "failed to get PHY lock: %d\n", ret);
+               clk_disable_unprepare(priv->phy_ref_clk);
+       }
+       mutex_unlock(&priv->lock);
+
+       return ret;
+}
+
+static int mixel_lvds_phy_power_off(struct phy *phy)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(phy->dev.parent);
+       struct mixel_lvds_phy *lvds_phy = phy_get_drvdata(phy);
+       struct mixel_lvds_phy *companion = priv->phys[lvds_phy->id ^ 1];
+       struct phy_configure_opts_lvds *cfg = &lvds_phy->cfg;
+
+       /* The master PHY would power off the slave PHY. */
+       if (cfg->is_slave)
+               return 0;
+
+       mutex_lock(&priv->lock);
+       if (companion->cfg.is_slave)
+               regmap_write(priv->regmap, PHY_CTRL + REG_CLR,
+                            CH_EN(0) | CH_EN(1));
+       else
+               regmap_write(priv->regmap, PHY_CTRL + REG_CLR,
+                            CH_EN(lvds_phy->id));
+       mutex_unlock(&priv->lock);
+
+       clk_disable_unprepare(priv->phy_ref_clk);
+
+       return 0;
+}
+
+static int mixel_lvds_phy_configure(struct phy *phy,
+                                   union phy_configure_opts *opts)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(phy->dev.parent);
+       struct phy_configure_opts_lvds *cfg = &opts->lvds;
+       int ret;
+
+       ret = clk_set_rate(priv->phy_ref_clk, cfg->differential_clk_rate);
+       if (ret)
+               dev_err(&phy->dev, "failed to set PHY reference clock rate(%lu): %d\n",
+                       cfg->differential_clk_rate, ret);
+
+       return ret;
+}
+
+/* Assume the master PHY's configuration set is cached first. */
+static int mixel_lvds_phy_check_slave(struct phy *slave_phy)
+{
+       struct device *dev = &slave_phy->dev;
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(dev->parent);
+       struct mixel_lvds_phy *slv = phy_get_drvdata(slave_phy);
+       struct mixel_lvds_phy *mst = priv->phys[slv->id ^ 1];
+       struct phy_configure_opts_lvds *mst_cfg = &mst->cfg;
+       struct phy_configure_opts_lvds *slv_cfg = &slv->cfg;
+
+       if (mst_cfg->bits_per_lane_and_dclk_cycle !=
+           slv_cfg->bits_per_lane_and_dclk_cycle) {
+               dev_err(dev, "number bits mismatch(mst: %u vs slv: %u)\n",
+                       mst_cfg->bits_per_lane_and_dclk_cycle,
+                       slv_cfg->bits_per_lane_and_dclk_cycle);
+               return -EINVAL;
+       }
+
+       if (mst_cfg->differential_clk_rate !=
+           slv_cfg->differential_clk_rate) {
+               dev_err(dev, "dclk rate mismatch(mst: %lu vs slv: %lu)\n",
+                       mst_cfg->differential_clk_rate,
+                       slv_cfg->differential_clk_rate);
+               return -EINVAL;
+       }
+
+       if (mst_cfg->lanes != slv_cfg->lanes) {
+               dev_err(dev, "lanes mismatch(mst: %u vs slv: %u)\n",
+                       mst_cfg->lanes, slv_cfg->lanes);
+               return -EINVAL;
+       }
+
+       if (mst_cfg->is_slave == slv_cfg->is_slave) {
+               dev_err(dev, "master PHY is not found\n");
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int mixel_lvds_phy_validate(struct phy *phy, enum phy_mode mode,
+                                  int submode, union phy_configure_opts *opts)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(phy->dev.parent);
+       struct mixel_lvds_phy *lvds_phy = phy_get_drvdata(phy);
+       struct phy_configure_opts_lvds *cfg = &opts->lvds;
+       int ret = 0;
+
+       if (mode != PHY_MODE_LVDS) {
+               dev_err(&phy->dev, "invalid PHY mode(%d)\n", mode);
+               return -EINVAL;
+       }
+
+       if (cfg->bits_per_lane_and_dclk_cycle != 7 &&
+           cfg->bits_per_lane_and_dclk_cycle != 10) {
+               dev_err(&phy->dev, "invalid bits per data lane(%u)\n",
+                       cfg->bits_per_lane_and_dclk_cycle);
+               return -EINVAL;
+       }
+
+       if (cfg->lanes != 4 && cfg->lanes != 3) {
+               dev_err(&phy->dev, "invalid data lanes(%u)\n", cfg->lanes);
+               return -EINVAL;
+       }
+
+       if (cfg->differential_clk_rate < MIN_CLKIN_FREQ ||
+           cfg->differential_clk_rate > MAX_CLKIN_FREQ) {
+               dev_err(&phy->dev, "invalid differential clock rate(%lu)\n",
+                       cfg->differential_clk_rate);
+               return -EINVAL;
+       }
+
+       mutex_lock(&priv->lock);
+       /* cache configuration set of our own for check */
+       memcpy(&lvds_phy->cfg, cfg, sizeof(*cfg));
+
+       if (cfg->is_slave) {
+               ret = mixel_lvds_phy_check_slave(phy);
+               if (ret)
+                       dev_err(&phy->dev, "failed to check slave PHY: %d\n", ret);
+       }
+       mutex_unlock(&priv->lock);
+
+       return ret;
+}
+
+static const struct phy_ops mixel_lvds_phy_ops = {
+       .init = mixel_lvds_phy_init,
+       .power_on = mixel_lvds_phy_power_on,
+       .power_off = mixel_lvds_phy_power_off,
+       .configure = mixel_lvds_phy_configure,
+       .validate = mixel_lvds_phy_validate,
+       .owner = THIS_MODULE,
+};
+
+static int mixel_lvds_phy_reset(struct device *dev)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(dev);
+       int ret;
+
+       ret = pm_runtime_resume_and_get(dev);
+       if (ret < 0) {
+               dev_err(dev, "failed to get PM runtime: %d\n", ret);
+               return ret;
+       }
+
+       regmap_write(priv->regmap, PHY_CTRL, CTRL_RESET_VAL);
+
+       ret = pm_runtime_put(dev);
+       if (ret < 0)
+               dev_err(dev, "failed to put PM runtime: %d\n", ret);
+
+       return ret;
+}
+
+static struct phy *mixel_lvds_phy_xlate(struct device *dev,
+                                       struct of_phandle_args *args)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(dev);
+       unsigned int phy_id;
+
+       if (args->args_count != 1) {
+               dev_err(dev,
+                       "invalid argument number(%d) for 'phys' property\n",
+                       args->args_count);
+               return ERR_PTR(-EINVAL);
+       }
+
+       phy_id = args->args[0];
+
+       if (phy_id >= PHY_NUM) {
+               dev_err(dev, "invalid PHY index(%d)\n", phy_id);
+               return ERR_PTR(-ENODEV);
+       }
+
+       return priv->phys[phy_id]->phy;
+}
+
+static int mixel_lvds_phy_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct phy_provider *phy_provider;
+       struct mixel_lvds_phy_priv *priv;
+       struct mixel_lvds_phy *lvds_phy;
+       struct phy *phy;
+       int i;
+       int ret;
+
+       if (!dev->of_node)
+               return -ENODEV;
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       priv->regmap = syscon_node_to_regmap(dev->of_node->parent);
+       if (IS_ERR(priv->regmap))
+               return dev_err_probe(dev, PTR_ERR(priv->regmap),
+                                    "failed to get regmap\n");
+
+       priv->phy_ref_clk = devm_clk_get(dev, NULL);
+       if (IS_ERR(priv->phy_ref_clk))
+               return dev_err_probe(dev, PTR_ERR(priv->phy_ref_clk),
+                                    "failed to get PHY reference clock\n");
+
+       mutex_init(&priv->lock);
+
+       dev_set_drvdata(dev, priv);
+
+       pm_runtime_enable(dev);
+
+       ret = mixel_lvds_phy_reset(dev);
+       if (ret) {
+               dev_err(dev, "failed to do POR reset: %d\n", ret);
+               return ret;
+       }
+
+       for (i = 0; i < PHY_NUM; i++) {
+               lvds_phy = devm_kzalloc(dev, sizeof(*lvds_phy), GFP_KERNEL);
+               if (!lvds_phy) {
+                       ret = -ENOMEM;
+                       goto err;
+               }
+
+               phy = devm_phy_create(dev, NULL, &mixel_lvds_phy_ops);
+               if (IS_ERR(phy)) {
+                       ret = PTR_ERR(phy);
+                       dev_err(dev, "failed to create PHY for channel%d: %d\n",
+                               i, ret);
+                       goto err;
+               }
+
+               lvds_phy->phy = phy;
+               lvds_phy->id = i;
+               priv->phys[i] = lvds_phy;
+
+               phy_set_drvdata(phy, lvds_phy);
+       }
+
+       phy_provider = devm_of_phy_provider_register(dev, mixel_lvds_phy_xlate);
+       if (IS_ERR(phy_provider)) {
+               ret = PTR_ERR(phy_provider);
+               dev_err(dev, "failed to register PHY provider: %d\n", ret);
+               goto err;
+       }
+
+       return 0;
+err:
+       pm_runtime_disable(dev);
+
+       return ret;
+}
+
+static int mixel_lvds_phy_remove(struct platform_device *pdev)
+{
+       pm_runtime_disable(&pdev->dev);
+
+       return 0;
+}
+
+static int __maybe_unused mixel_lvds_phy_runtime_suspend(struct device *dev)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(dev);
+
+       /* power down */
+       mutex_lock(&priv->lock);
+       regmap_write(priv->regmap, PHY_CTRL + REG_SET, PD);
+       mutex_unlock(&priv->lock);
+
+       return 0;
+}
+
+static int __maybe_unused mixel_lvds_phy_runtime_resume(struct device *dev)
+{
+       struct mixel_lvds_phy_priv *priv = dev_get_drvdata(dev);
+
+       /* power up + control initialization */
+       mutex_lock(&priv->lock);
+       regmap_update_bits(priv->regmap, PHY_CTRL,
+                          CTRL_INIT_MASK | PD, CTRL_INIT_VAL);
+       mutex_unlock(&priv->lock);
+
+       return 0;
+}
+
+static const struct dev_pm_ops mixel_lvds_phy_pm_ops = {
+       SET_RUNTIME_PM_OPS(mixel_lvds_phy_runtime_suspend,
+                          mixel_lvds_phy_runtime_resume, NULL)
+};
+
+static const struct of_device_id mixel_lvds_phy_of_match[] = {
+       { .compatible = "fsl,imx8qm-lvds-phy" },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mixel_lvds_phy_of_match);
+
+static struct platform_driver mixel_lvds_phy_driver = {
+       .probe  = mixel_lvds_phy_probe,
+       .remove = mixel_lvds_phy_remove,
+       .driver = {
+               .pm = &mixel_lvds_phy_pm_ops,
+               .name = "mixel-lvds-phy",
+               .of_match_table = mixel_lvds_phy_of_match,
+       }
+};
+module_platform_driver(mixel_lvds_phy_driver);
+
+MODULE_DESCRIPTION("Mixel LVDS PHY driver");
+MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
+MODULE_LICENSE("GPL");