[PATCH v2 2/2] phy: amlogic: Add a new driver for the HDMI TX PHY on Meson8/8b/8m2

Martin Blumenstingl
2021-06-29T18:21:17Z

Amlogic Meson8/8b/8m2 have a built-in HDMI PHY in the HHI register
region. Unfortunately only few register bits are documented. For
HHI_HDMI_PHY_CNTL0 the magic numbers are taken from the 3.10 vendor
kernel.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
drivers/phy/amlogic/Kconfig | 10 ++
drivers/phy/amlogic/Makefile | 1 +
drivers/phy/amlogic/phy-meson8-hdmi-tx.c | 162 +++++++++++++++++++++++
3 files changed, 173 insertions(+)
create mode 100644 drivers/phy/amlogic/phy-meson8-hdmi-tx.c

diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
index db5d0cd757e3..486ca23aba32 100644
--- a/drivers/phy/amlogic/Kconfig
+++ b/drivers/phy/amlogic/Kconfig
@@ -2,6 +2,16 @@
#
# Phy drivers for Amlogic platforms
#
+config PHY_MESON8_HDMI_TX
+ tristate "Meson8, Meson8b and Meson8m2 HDMI TX PHY driver"
+ depends on (ARCH_MESON && ARM) || COMPILE_TEST
+ depends on OF
+ select MFD_SYSCON
+ help
+ Enable this to support the HDMI TX PHYs found in Meson8,
+ Meson8b and Meson8m2 SoCs.
+ If unsure, say N.
+
config PHY_MESON8B_USB2
tristate "Meson8, Meson8b, Meson8m2 and GXBB USB2 PHY driver"
default ARCH_MESON
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index 8fa07fbd0d92..c0886c850bb0 100644
--- a/drivers/phy/amlogic/Makefile
+++ b/drivers/phy/amlogic/Makefile
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_PHY_MESON8_HDMI_TX) += phy-meson8-hdmi-tx.o
obj-$(CONFIG_PHY_MESON8B_USB2) += phy-meson8b-usb2.o
obj-$(CONFIG_PHY_MESON_GXL_USB2) += phy-meson-gxl-usb2.o
obj-$(CONFIG_PHY_MESON_G12A_USB2) += phy-meson-g12a-usb2.o
diff --git a/drivers/phy/amlogic/phy-meson8-hdmi-tx.c b/drivers/phy/amlogic/phy-meson8-hdmi-tx.c
new file mode 100644
index 000000000000..ba5a4de54811
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson8-hdmi-tx.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Meson8, Meson8b and Meson8m2 HDMI TX PHY.
+ *
+ * Copyright (C) 2021 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#define HHI_HDMI_PHY_CNTL0 0x0
+ #define HHI_HDMI_PHY_CNTL0_HDMI_CTL1 GENMASK(31, 16)
+ #define HHI_HDMI_PHY_CNTL0_HDMI_CTL0 GENMASK(15, 0)
+
+#define HHI_HDMI_PHY_CNTL1 0x4
+ #define HHI_HDMI_PHY_CNTL1_CLOCK_ENABLE BIT(1)
+ #define HHI_HDMI_PHY_CNTL1_SOFT_RESET BIT(0)
+
+#define HHI_HDMI_PHY_CNTL2 0x8
+
+struct phy_meson8_hdmi_tx_priv {
+ struct regmap *hhi;
+ struct clk *tmds_clk;
+ unsigned int reg_offset;
+};
+
+static int phy_meson8_hdmi_tx_init(struct phy *phy)
+{
+ struct phy_meson8_hdmi_tx_priv *priv = phy_get_drvdata(phy);
+
+ return clk_prepare_enable(priv->tmds_clk);
+}
+
+static int phy_meson8_hdmi_tx_exit(struct phy *phy)
+{
+ struct phy_meson8_hdmi_tx_priv *priv = phy_get_drvdata(phy);
+
+ clk_disable_unprepare(priv->tmds_clk);
+
+ return 0;
+}
+
+static int phy_meson8_hdmi_tx_power_on(struct phy *phy)
+{
+ struct phy_meson8_hdmi_tx_priv *priv = phy_get_drvdata(phy);
+ unsigned int i;
+ u16 hdmi_ctl0;
+
+ if (clk_get_rate(priv->tmds_clk) >= 2970UL * 1000 * 1000)
+ hdmi_ctl0 = 0x1e8b;
+ else
+ hdmi_ctl0 = 0x4d0b;
+
+ regmap_write(priv->hhi, priv->reg_offset + HHI_HDMI_PHY_CNTL0,
+ FIELD_PREP(HHI_HDMI_PHY_CNTL0_HDMI_CTL1, 0x08c3) |
+ FIELD_PREP(HHI_HDMI_PHY_CNTL0_HDMI_CTL0, hdmi_ctl0));
+
+ regmap_write(priv->hhi, priv->reg_offset + HHI_HDMI_PHY_CNTL1, 0x0);
+
+ /* Reset three times, just like the vendor driver does */
+ for (i = 0; i < 3; i++) {
+ regmap_write(priv->hhi, priv->reg_offset + HHI_HDMI_PHY_CNTL1,
+ HHI_HDMI_PHY_CNTL1_CLOCK_ENABLE |
+ HHI_HDMI_PHY_CNTL1_SOFT_RESET);
+ usleep_range(1000, 2000);
+
+ regmap_write(priv->hhi, priv->reg_offset + HHI_HDMI_PHY_CNTL1,
+ HHI_HDMI_PHY_CNTL1_CLOCK_ENABLE);
+ usleep_range(1000, 2000);
+ }
+
+ return 0;
+}
+
+static int phy_meson8_hdmi_tx_power_off(struct phy *phy)
+{
+ struct phy_meson8_hdmi_tx_priv *priv = phy_get_drvdata(phy);
+
+ regmap_write(priv->hhi, priv->reg_offset + HHI_HDMI_PHY_CNTL0,
+ FIELD_PREP(HHI_HDMI_PHY_CNTL0_HDMI_CTL1, 0x0841) |
+ FIELD_PREP(HHI_HDMI_PHY_CNTL0_HDMI_CTL0, 0x8d00));
+
+ return 0;
+}
+
+static const struct phy_ops phy_meson8_hdmi_tx_ops = {
+ .init = phy_meson8_hdmi_tx_init,
+ .exit = phy_meson8_hdmi_tx_exit,
+ .power_on = phy_meson8_hdmi_tx_power_on,
+ .power_off = phy_meson8_hdmi_tx_power_off,
+ .owner = THIS_MODULE,
+};
+
+static int phy_meson8_hdmi_tx_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct phy_meson8_hdmi_tx_priv *priv;
+ struct phy_provider *phy_provider;
+ struct phy *phy;
+ u32 reg[2];
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ ret = device_property_read_u32_array(&pdev->dev, "reg", reg,
+ ARRAY_SIZE(reg));
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret,
+ "Failed to parse the 'reg' property\n");
+
+ priv->reg_offset = reg[0];
+
+ priv->hhi = syscon_node_to_regmap(np->parent);
+ if (IS_ERR(priv->hhi))
+ return PTR_ERR(priv->hhi);
+
+ priv->tmds_clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(priv->tmds_clk))
+ return PTR_ERR(priv->tmds_clk);
+
+ phy = devm_phy_create(&pdev->dev, np, &phy_meson8_hdmi_tx_ops);
+ if (IS_ERR(phy))
+ return PTR_ERR(phy);
+
+ phy_set_drvdata(phy, priv);
+
+ phy_provider = devm_of_phy_provider_register(&pdev->dev,
+ of_phy_simple_xlate);
+
+ return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id phy_meson8_hdmi_tx_of_match[] = {
+ { .compatible = "amlogic,meson8-hdmi-tx-phy" },
+ { .compatible = "amlogic,meson8b-hdmi-tx-phy" },
+ { .compatible = "amlogic,meson8m2-hdmi-tx-phy" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, phy_meson8_hdmi_tx_of_match);
+
+static struct platform_driver phy_meson8_hdmi_tx_driver = {
+ .probe = phy_meson8_hdmi_tx_probe,
+ .driver = {
+ .name = "phy-meson8-hdmi-tx",
+ .of_match_table = phy_meson8_hdmi_tx_of_match,
+ },
+};
+module_platform_driver(phy_meson8_hdmi_tx_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Meson8, Meson8b and Meson8m2 HDMI TX PHY driver");
+MODULE_LICENSE("GPL v2");
--
2.32.0