[PATCH v3 2/2] phy: stm32: add support for STM32 USB PHY Controller (USBPHYC)
Amelie Delaunay
amelie.delaunay at st.com
Fri Mar 2 06:56:25 PST 2018
This patch adds phy transceiver driver for STM32 USB PHY Controller
(USBPHYC) that provides dual port High-Speed phy for OTG (single port)
and EHCI/OHCI host controller (two ports).
One port of the phy is shared between the two USB controllers through
a UTMI+ switch.
Signed-off-by: Amelie Delaunay <amelie.delaunay at st.com>
---
drivers/phy/st/Kconfig | 14 ++
drivers/phy/st/Makefile | 1 +
drivers/phy/st/phy-stm32-usbphyc.c | 461 +++++++++++++++++++++++++++++++++++++
3 files changed, 476 insertions(+)
create mode 100644 drivers/phy/st/phy-stm32-usbphyc.c
diff --git a/drivers/phy/st/Kconfig b/drivers/phy/st/Kconfig
index 0814d3f..609719b 100644
--- a/drivers/phy/st/Kconfig
+++ b/drivers/phy/st/Kconfig
@@ -31,3 +31,17 @@ config PHY_STIH407_USB
help
Enable this support to enable the picoPHY device used by USB2
and USB3 controllers on STMicroelectronics STiH407 SoC families.
+
+config PHY_STM32_USBPHYC
+ tristate "STMicroelectronics STM32 USB HS PHY Controller driver"
+ depends on ARCH_STM32 || COMPILE_TEST
+ select GENERIC_PHY
+ help
+ Enable this to support the High-Speed USB transceivers that are part
+ of some STMicroelectronics STM32 SoCs.
+
+ This driver controls the entire USB PHY block: the USB PHY controller
+ (USBPHYC) and the two 8-bit wide UTMI+ interfaces. First interface is
+ used by an HS USB Host controller, and the second one is shared
+ between an HS USB OTG controller and an HS USB Host controller,
+ selected by a USB switch.
diff --git a/drivers/phy/st/Makefile b/drivers/phy/st/Makefile
index e2adfe2..c0091ad 100644
--- a/drivers/phy/st/Makefile
+++ b/drivers/phy/st/Makefile
@@ -2,3 +2,4 @@ obj-$(CONFIG_PHY_MIPHY28LP) += phy-miphy28lp.o
obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY) += phy-spear1310-miphy.o
obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY) += phy-spear1340-miphy.o
obj-$(CONFIG_PHY_STIH407_USB) += phy-stih407-usb.o
+obj-$(CONFIG_PHY_STM32_USBPHYC) += phy-stm32-usbphyc.o
diff --git a/drivers/phy/st/phy-stm32-usbphyc.c b/drivers/phy/st/phy-stm32-usbphyc.c
new file mode 100644
index 0000000..1b2ac25
--- /dev/null
+++ b/drivers/phy/st/phy-stm32-usbphyc.c
@@ -0,0 +1,461 @@
+// SPDX-Licence-Identifier: GPL-2.0
+/*
+ * STMicroelectronics STM32 USB PHY Controller driver
+ *
+ * Copyright (C) 2018 STMicroelectronics
+ * Author(s): Amelie Delaunay <amelie.delaunay at st.com>.
+ */
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/phy/phy.h>
+#include <linux/reset.h>
+
+#define STM32_USBPHYC_PLL 0x0
+#define STM32_USBPHYC_MISC 0x8
+#define STM32_USBPHYC_VERSION 0x3F4
+
+/* STM32_USBPHYC_PLL bit fields */
+#define PLLNDIV GENMASK(6, 0)
+#define PLLFRACIN GENMASK(25, 10)
+#define PLLEN BIT(26)
+#define PLLSTRB BIT(27)
+#define PLLSTRBYP BIT(28)
+#define PLLFRACCTL BIT(29)
+#define PLLDITHEN0 BIT(30)
+#define PLLDITHEN1 BIT(31)
+
+/* STM32_USBPHYC_MISC bit fields */
+#define SWITHOST BIT(0)
+
+/* STM32_USBPHYC_VERSION bit fields */
+#define MINREV GENMASK(3, 0)
+#define MAJREV GENMASK(7, 4)
+
+static const char * const supplies_names[] = {
+ "vdda1v1", /* 1V1 */
+ "vdda1v8", /* 1V8 */
+};
+
+#define NUM_SUPPLIES ARRAY_SIZE(supplies_names)
+
+#define PLL_LOCK_TIME_US 100
+#define PLL_PWR_DOWN_TIME_US 5
+#define PLL_FVCO_MHZ 2880
+#define PLL_INFF_MIN_RATE_HZ 19200000
+#define PLL_INFF_MAX_RATE_HZ 38400000
+#define HZ_PER_MHZ 1000000L
+
+struct pll_params {
+ u8 ndiv;
+ u16 frac;
+};
+
+struct stm32_usbphyc_phy {
+ struct phy *phy;
+ struct stm32_usbphyc *usbphyc;
+ struct regulator_bulk_data supplies[NUM_SUPPLIES];
+ u32 index;
+ bool active;
+};
+
+struct stm32_usbphyc {
+ struct device *dev;
+ void __iomem *base;
+ struct clk *clk;
+ struct reset_control *rst;
+ struct stm32_usbphyc_phy **phys;
+ int nphys;
+ int switch_setup;
+ bool pll_enabled;
+};
+
+static inline void stm32_usbphyc_set_bits(void __iomem *reg, u32 bits)
+{
+ writel_relaxed(readl_relaxed(reg) | bits, reg);
+}
+
+static inline void stm32_usbphyc_clr_bits(void __iomem *reg, u32 bits)
+{
+ writel_relaxed(readl_relaxed(reg) & ~bits, reg);
+}
+
+void stm32_usbphyc_get_pll_params(u32 clk_rate, struct pll_params *pll_params)
+{
+ unsigned long long fvco, ndiv, frac;
+
+ /* _
+ * | FVCO = INFF*2*(NDIV + FRACT/2^16) when DITHER_DISABLE[1] = 1
+ * | FVCO = 2880MHz
+ * <
+ * | NDIV = integer part of input bits to set the LDF
+ * |_FRACT = fractional part of input bits to set the LDF
+ * => PLLNDIV = integer part of (FVCO / (INFF*2))
+ * => PLLFRACIN = fractional part of(FVCO / INFF*2) * 2^16
+ * <=> PLLFRACIN = ((FVCO / (INFF*2)) - PLLNDIV) * 2^16
+ */
+ fvco = (unsigned long long)PLL_FVCO_MHZ * HZ_PER_MHZ;
+
+ ndiv = fvco;
+ do_div(ndiv, (clk_rate * 2));
+ pll_params->ndiv = (u8)ndiv;
+
+ frac = fvco * (1 << 16);
+ do_div(frac, (clk_rate * 2));
+ frac = frac - (ndiv * (1 << 16));
+ pll_params->frac = (u16)frac;
+}
+
+static int stm32_usbphyc_pll_init(struct stm32_usbphyc *usbphyc)
+{
+ struct pll_params pll_params;
+ u32 clk_rate = clk_get_rate(usbphyc->clk);
+ u32 ndiv, frac;
+ u32 usbphyc_pll;
+
+ if ((clk_rate < PLL_INFF_MIN_RATE_HZ) ||
+ (clk_rate > PLL_INFF_MAX_RATE_HZ)) {
+ dev_err(usbphyc->dev, "input clk freq (%dHz) out of range\n",
+ clk_rate);
+ return -EINVAL;
+ }
+
+ stm32_usbphyc_get_pll_params(clk_rate, &pll_params);
+ ndiv = FIELD_PREP(PLLNDIV, pll_params.ndiv);
+ frac = FIELD_PREP(PLLFRACIN, pll_params.frac);
+
+ usbphyc_pll = PLLDITHEN1 | PLLDITHEN0 | PLLSTRBYP | ndiv;
+
+ if (pll_params.frac)
+ usbphyc_pll |= PLLFRACCTL | frac;
+
+ writel_relaxed(usbphyc_pll, usbphyc->base + STM32_USBPHYC_PLL);
+
+ dev_dbg(usbphyc->dev, "input clk freq=%dHz, ndiv=%lu, frac=%lu\n",
+ clk_rate, FIELD_GET(PLLNDIV, usbphyc_pll),
+ FIELD_GET(PLLFRACIN, usbphyc_pll));
+
+ return 0;
+}
+
+static bool stm32_usbphyc_has_one_phy_active(struct stm32_usbphyc *usbphyc)
+{
+ int i;
+
+ for (i = 0; i < usbphyc->nphys; i++)
+ if (usbphyc->phys[i]->active)
+ return true;
+
+ return false;
+}
+
+static int stm32_usbphyc_pll_enable(struct stm32_usbphyc *usbphyc)
+{
+ void __iomem *pll_reg = usbphyc->base + STM32_USBPHYC_PLL;
+ bool pllen = (readl_relaxed(pll_reg) & PLLEN);
+ int ret;
+
+ /* Check if one phy port has already configured the pll */
+ if (pllen && stm32_usbphyc_has_one_phy_active(usbphyc))
+ return 0;
+
+ if (pllen) {
+ stm32_usbphyc_clr_bits(pll_reg, PLLEN);
+ /* Wait for minimum width of powerdown pulse (ENABLE = Low) */
+ udelay(PLL_PWR_DOWN_TIME_US);
+ }
+
+ ret = stm32_usbphyc_pll_init(usbphyc);
+ if (ret)
+ return ret;
+
+ stm32_usbphyc_set_bits(pll_reg, PLLEN);
+
+ /* Wait for maximum lock time */
+ udelay(PLL_LOCK_TIME_US);
+
+ if (!(readl_relaxed(pll_reg) & PLLEN)) {
+ dev_err(usbphyc->dev, "PLLEN not set\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int stm32_usbphyc_pll_disable(struct stm32_usbphyc *usbphyc)
+{
+ void __iomem *pll_reg = usbphyc->base + STM32_USBPHYC_PLL;
+
+ /* Check if other phy port active */
+ if (stm32_usbphyc_has_one_phy_active(usbphyc))
+ return 0;
+
+ stm32_usbphyc_clr_bits(pll_reg, PLLEN);
+ /* Wait for minimum width of powerdown pulse (ENABLE = Low) */
+ udelay(PLL_PWR_DOWN_TIME_US);
+
+ if (readl_relaxed(pll_reg) & PLLEN) {
+ dev_err(usbphyc->dev, "PLL not reset\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int stm32_usbphyc_phy_init(struct phy *phy)
+{
+ struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
+ struct stm32_usbphyc *usbphyc = usbphyc_phy->usbphyc;
+ int ret;
+
+ ret = stm32_usbphyc_pll_enable(usbphyc);
+ if (ret)
+ return ret;
+
+ usbphyc_phy->active = true;
+
+ return 0;
+}
+
+static int stm32_usbphyc_phy_exit(struct phy *phy)
+{
+ struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
+ struct stm32_usbphyc *usbphyc = usbphyc_phy->usbphyc;
+
+ usbphyc_phy->active = false;
+
+ return stm32_usbphyc_pll_disable(usbphyc);
+}
+
+static int stm32_usbphyc_phy_power_on(struct phy *phy)
+{
+ struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
+
+ return regulator_bulk_enable(NUM_SUPPLIES, usbphyc_phy->supplies);
+}
+
+static int stm32_usbphyc_phy_power_off(struct phy *phy)
+{
+ struct stm32_usbphyc_phy *usbphyc_phy = phy_get_drvdata(phy);
+
+ return regulator_bulk_disable(NUM_SUPPLIES, usbphyc_phy->supplies);
+}
+
+static const struct phy_ops stm32_usbphyc_phy_ops = {
+ .init = stm32_usbphyc_phy_init,
+ .exit = stm32_usbphyc_phy_exit,
+ .power_on = stm32_usbphyc_phy_power_on,
+ .power_off = stm32_usbphyc_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static void stm32_usbphyc_switch_setup(struct stm32_usbphyc *usbphyc,
+ u32 utmi_switch)
+{
+ if (!utmi_switch)
+ stm32_usbphyc_clr_bits(usbphyc->base + STM32_USBPHYC_MISC,
+ SWITHOST);
+ else
+ stm32_usbphyc_set_bits(usbphyc->base + STM32_USBPHYC_MISC,
+ SWITHOST);
+ usbphyc->switch_setup = utmi_switch;
+}
+
+static struct phy *stm32_usbphyc_of_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct stm32_usbphyc *usbphyc = dev_get_drvdata(dev);
+ struct stm32_usbphyc_phy *usbphyc_phy = NULL;
+ struct device_node *phynode = args->np;
+
+ int port = 0;
+
+ for (port = 0; port < usbphyc->nphys; port++) {
+ if (phynode == usbphyc->phys[port]->phy->dev.of_node) {
+ usbphyc_phy = usbphyc->phys[port];
+ break;
+ }
+ }
+ if (!usbphyc_phy) {
+ dev_err(dev, "failed to find phy\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (((usbphyc_phy->index == 0) && (args->args_count != 0)) ||
+ ((usbphyc_phy->index == 1) && (args->args_count != 1))) {
+ dev_err(dev, "invalid number of cells for phy port%d\n",
+ usbphyc_phy->index);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* Configure the UTMI switch for PHY port#2 */
+ if (usbphyc_phy->index == 1) {
+ if (usbphyc->switch_setup < 0) {
+ stm32_usbphyc_switch_setup(usbphyc, args->args[0]);
+ } else {
+ if (args->args[0] != usbphyc->switch_setup) {
+ dev_err(dev, "phy port1 already used\n");
+ return ERR_PTR(-EBUSY);
+ }
+ }
+ }
+
+ return usbphyc_phy->phy;
+}
+
+static int stm32_usbphyc_probe(struct platform_device *pdev)
+{
+ struct stm32_usbphyc *usbphyc;
+ struct device *dev = &pdev->dev;
+ struct device_node *child, *np = dev->of_node;
+ struct resource *res;
+ struct phy_provider *phy_provider;
+ u32 version;
+ int ret, port = 0;
+
+ usbphyc = devm_kzalloc(dev, sizeof(*usbphyc), GFP_KERNEL);
+ if (!usbphyc)
+ return -ENOMEM;
+ usbphyc->dev = dev;
+ dev_set_drvdata(dev, usbphyc);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ usbphyc->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(usbphyc->base))
+ return PTR_ERR(usbphyc->base);
+
+ usbphyc->clk = devm_clk_get(dev, 0);
+ if (IS_ERR(usbphyc->clk)) {
+ ret = PTR_ERR(usbphyc->clk);
+ dev_err(dev, "clk get failed: %d\n", ret);
+ return ret;
+ }
+
+ ret = clk_prepare_enable(usbphyc->clk);
+ if (ret) {
+ dev_err(dev, "clk enable failed: %d\n", ret);
+ return ret;
+ }
+
+ usbphyc->rst = devm_reset_control_get(dev, 0);
+ if (!IS_ERR(usbphyc->rst)) {
+ reset_control_assert(usbphyc->rst);
+ udelay(2);
+ reset_control_deassert(usbphyc->rst);
+ }
+
+ usbphyc->switch_setup = -EINVAL;
+ usbphyc->nphys = of_get_child_count(np);
+ usbphyc->phys = devm_kcalloc(dev, usbphyc->nphys,
+ sizeof(*usbphyc->phys), GFP_KERNEL);
+ if (!usbphyc->phys) {
+ ret = -ENOMEM;
+ goto clk_disable;
+ }
+
+ for_each_child_of_node(np, child) {
+ struct stm32_usbphyc_phy *usbphyc_phy;
+ struct phy *phy;
+ u32 index;
+ int i;
+
+ phy = devm_phy_create(dev, child, &stm32_usbphyc_phy_ops);
+ if (IS_ERR(phy)) {
+ ret = PTR_ERR(phy);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev,
+ "failed to create phy%d: %d\n", i, ret);
+ goto put_child;
+ }
+
+ usbphyc_phy = devm_kzalloc(dev, sizeof(*usbphyc_phy),
+ GFP_KERNEL);
+ if (!usbphyc_phy) {
+ ret = -ENOMEM;
+ goto put_child;
+ }
+
+ for (i = 0; i < NUM_SUPPLIES; i++)
+ usbphyc_phy->supplies[i].supply = supplies_names[i];
+
+ ret = devm_regulator_bulk_get(&phy->dev, NUM_SUPPLIES,
+ usbphyc_phy->supplies);
+ if (ret) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(&phy->dev,
+ "failed to get regulators: %d\n", ret);
+ goto put_child;
+ }
+
+ ret = of_property_read_u32(child, "reg", &index);
+ if (ret || index > usbphyc->nphys) {
+ dev_err(&phy->dev, "invalid reg property: %d\n", ret);
+ goto put_child;
+ }
+
+ usbphyc->phys[port] = usbphyc_phy;
+ phy_set_bus_width(phy, 8);
+ phy_set_drvdata(phy, usbphyc_phy);
+
+ usbphyc->phys[port]->phy = phy;
+ usbphyc->phys[port]->usbphyc = usbphyc;
+ usbphyc->phys[port]->index = index;
+ usbphyc->phys[port]->active = false;
+
+ port++;
+ }
+
+ phy_provider = devm_of_phy_provider_register(dev,
+ stm32_usbphyc_of_xlate);
+ if (IS_ERR(phy_provider)) {
+ ret = PTR_ERR(phy_provider);
+ dev_err(dev, "failed to register phy provider: %d\n", ret);
+ goto clk_disable;
+ }
+
+ version = readl_relaxed(usbphyc->base + STM32_USBPHYC_VERSION);
+ dev_info(dev, "registered rev:%lu.%lu\n",
+ FIELD_GET(MAJREV, version), FIELD_GET(MINREV, version));
+
+ return 0;
+
+put_child:
+ of_node_put(child);
+clk_disable:
+ clk_disable_unprepare(usbphyc->clk);
+
+ return ret;
+}
+
+static int stm32_usbphyc_remove(struct platform_device *pdev)
+{
+ struct stm32_usbphyc *usbphyc = dev_get_drvdata(&pdev->dev);
+
+ clk_disable_unprepare(usbphyc->clk);
+
+ return 0;
+}
+
+static const struct of_device_id stm32_usbphyc_of_match[] = {
+ { .compatible = "st,stm32mp1-usbphyc", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, stm32_usbphyc_of_match);
+
+static struct platform_driver stm32_usbphyc_driver = {
+ .probe = stm32_usbphyc_probe,
+ .remove = stm32_usbphyc_remove,
+ .driver = {
+ .of_match_table = stm32_usbphyc_of_match,
+ .name = "stm32-usbphyc",
+ }
+};
+module_platform_driver(stm32_usbphyc_driver);
+
+MODULE_DESCRIPTION("STMicroelectronics STM32 USBPHYC driver");
+MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay at st.com>");
+MODULE_LICENSE("GPL v2");
--
2.7.4
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