phy: exynos5-usbdrd: gs101: configure SS lanes based on orientation

USB SS lanes need to be configured based on the connector orientation -
at most two lanes will be in use for USB (and the remaining two for
alternate modes like DP).

For the USB link to come up in SS, the lane configuration registers
have to be programmed accordingly.

While we still need a way to be notified of the actual connector
orientation and then reprogram the registers accordingly (at the moment
the configuration happens just once during phy_init() and never again),
we can prepare the code doing the configuration to take the orientation
into account.

Do so.

Note: the mutex is needed to synchronize this with the upcoming
connector orientation callback.

Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Tested-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Tested-by: Will McVicker <willmcvicker@google.com>
Link: https://lore.kernel.org/r/20241206-gs101-phy-lanes-orientation-phy-v4-5-f5961268b149@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
index 2a724d362c2da4bb072beecf2917f17dbc3a6bf3..61e0de4b3d4b266c5a3b63622550cd98258561ab 100644 (file)
--- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
+++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
@@ -23,6 +23,7 @@
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/soc/samsung/exynos-regs-pmu.h>
+#include <linux/usb/typec.h>
 
 /* Exynos USB PHY registers */
 #define EXYNOS5_FSEL_9MHZ6             0x0
@@ -209,6 +210,10 @@
 
 #define EXYNOS9_PMA_USBDP_CMN_REG00B8          0x02e0
 #define CMN_REG00B8_LANE_MUX_SEL_DP            GENMASK(3, 0)
+#define CMN_REG00B8_LANE_MUX_SEL_DP_LANE3      BIT(3)
+#define CMN_REG00B8_LANE_MUX_SEL_DP_LANE2      BIT(2)
+#define CMN_REG00B8_LANE_MUX_SEL_DP_LANE1      BIT(1)
+#define CMN_REG00B8_LANE_MUX_SEL_DP_LANE0      BIT(0)
 
 #define EXYNOS9_PMA_USBDP_CMN_REG01C0          0x0700
 #define CMN_REG01C0_ANA_LCPLL_LOCK_DONE                BIT(7)
@@ -383,11 +388,13 @@ struct exynos5_usbdrd_phy_drvdata {
  * @clks: clocks for register access
  * @core_clks: core clocks for phy (ref, pipe3, utmi+, ITP, etc. as required)
  * @drv_data: pointer to SoC level driver data structure
+ * @phy_mutex: mutex protecting phy_init/exit & TCPC callbacks
  * @phys: array for 'EXYNOS5_DRDPHYS_NUM' number of PHY
  *         instances each with its 'phy' and 'phy_cfg'.
  * @extrefclk: frequency select settings when using 'separate
  *            reference clocks' for SS and HS operations
  * @regulators: regulators for phy
+ * @orientation: TypeC connector orientation - normal or flipped
  */
 struct exynos5_usbdrd_phy {
        struct device *dev;
@@ -397,6 +404,7 @@ struct exynos5_usbdrd_phy {
        struct clk_bulk_data *clks;
        struct clk_bulk_data *core_clks;
        const struct exynos5_usbdrd_phy_drvdata *drv_data;
+       struct mutex phy_mutex;
        struct phy_usb_instance {
                struct phy *phy;
                u32 index;
@@ -406,6 +414,8 @@ struct exynos5_usbdrd_phy {
        } phys[EXYNOS5_DRDPHYS_NUM];
        u32 extrefclk;
        struct regulator_bulk_data *regulators;
+
+       enum typec_orientation orientation;
 };
 
 static inline
@@ -647,22 +657,38 @@ exynos5_usbdrd_usbdp_g2_v4_pma_lane_mux_sel(struct exynos5_usbdrd_phy *phy_drd)
        /* lane configuration: USB on all lanes */
        reg = readl(regs_base + EXYNOS9_PMA_USBDP_CMN_REG00B8);
        reg &= ~CMN_REG00B8_LANE_MUX_SEL_DP;
-       writel(reg, regs_base + EXYNOS9_PMA_USBDP_CMN_REG00B8);
-
        /*
-        * FIXME: below code supports one connector orientation only. It needs
-        * updating once we can receive connector events.
+        * USB on lanes 0 & 1 in normal mode, or 2 & 3 if reversed, DP on the
+        * other ones.
         */
+       reg |= FIELD_PREP(CMN_REG00B8_LANE_MUX_SEL_DP,
+                         ((phy_drd->orientation == TYPEC_ORIENTATION_NORMAL)
+                          ? (CMN_REG00B8_LANE_MUX_SEL_DP_LANE3
+                             | CMN_REG00B8_LANE_MUX_SEL_DP_LANE2)
+                          : (CMN_REG00B8_LANE_MUX_SEL_DP_LANE1
+                             | CMN_REG00B8_LANE_MUX_SEL_DP_LANE0)));
+       writel(reg, regs_base + EXYNOS9_PMA_USBDP_CMN_REG00B8);
+
        /* override of TX receiver detector and comparator: lane 1 */
        reg = readl(regs_base + EXYNOS9_PMA_USBDP_TRSV_REG0413);
-       reg &= ~TRSV_REG0413_OVRD_LN1_TX_RXD_COMP_EN;
-       reg &= ~TRSV_REG0413_OVRD_LN1_TX_RXD_EN;
+       if (phy_drd->orientation == TYPEC_ORIENTATION_NORMAL) {
+               reg &= ~TRSV_REG0413_OVRD_LN1_TX_RXD_COMP_EN;
+               reg &= ~TRSV_REG0413_OVRD_LN1_TX_RXD_EN;
+       } else {
+               reg |= TRSV_REG0413_OVRD_LN1_TX_RXD_COMP_EN;
+               reg |= TRSV_REG0413_OVRD_LN1_TX_RXD_EN;
+       }
        writel(reg, regs_base + EXYNOS9_PMA_USBDP_TRSV_REG0413);
 
        /* lane 3 */
        reg = readl(regs_base + EXYNOS9_PMA_USBDP_TRSV_REG0813);
-       reg |= TRSV_REG0813_OVRD_LN3_TX_RXD_COMP_EN;
-       reg |= TRSV_REG0813_OVRD_LN3_TX_RXD_EN;
+       if (phy_drd->orientation == TYPEC_ORIENTATION_NORMAL) {
+               reg |= TRSV_REG0813_OVRD_LN3_TX_RXD_COMP_EN;
+               reg |= TRSV_REG0813_OVRD_LN3_TX_RXD_EN;
+       } else {
+               reg &= ~TRSV_REG0813_OVRD_LN3_TX_RXD_COMP_EN;
+               reg &= ~TRSV_REG0813_OVRD_LN3_TX_RXD_EN;
+       }
        writel(reg, regs_base + EXYNOS9_PMA_USBDP_TRSV_REG0813);
 }
 
@@ -700,21 +726,18 @@ exynos5_usbdrd_usbdp_g2_v4_pma_check_cdr_lock(struct exynos5_usbdrd_phy *phy_drd
        int err;
 
        err = readl_poll_timeout(
-                       phy_drd->reg_pma + EXYNOS9_PMA_USBDP_TRSV_REG03C3,
-                       reg, (reg & locked) == locked, sleep_us, timeout_us);
-       if (!err)
-               return;
-
-       dev_err(phy_drd->dev,
-               "timed out waiting for CDR lock (l0): %#.8x, retrying\n", reg);
-
-       /* based on cable orientation, this might be on the other phy port */
-       err = readl_poll_timeout(
-                       phy_drd->reg_pma + EXYNOS9_PMA_USBDP_TRSV_REG07C3,
+                       /* lane depends on cable orientation */
+                       (phy_drd->reg_pma
+                        + ((phy_drd->orientation == TYPEC_ORIENTATION_NORMAL)
+                           ? EXYNOS9_PMA_USBDP_TRSV_REG03C3
+                           : EXYNOS9_PMA_USBDP_TRSV_REG07C3)),
                        reg, (reg & locked) == locked, sleep_us, timeout_us);
        if (err)
                dev_err(phy_drd->dev,
-                       "timed out waiting for CDR lock (l2): %#.8x\n", reg);
+                       "timed out waiting for CDR(l%d) lock: %#.8x\n",
+                       ((phy_drd->orientation == TYPEC_ORIENTATION_NORMAL)
+                        ? 0
+                        : 2), reg);
 }
 
 static void exynos5_usbdrd_utmi_init(struct exynos5_usbdrd_phy *phy_drd)
@@ -1184,7 +1207,8 @@ static int exynos850_usbdrd_phy_init(struct phy *phy)
                return ret;
 
        /* UTMI or PIPE3 specific init */
-       inst->phy_cfg->phy_init(phy_drd);
+       scoped_guard(mutex, &phy_drd->phy_mutex)
+               inst->phy_cfg->phy_init(phy_drd);
 
        clk_bulk_disable_unprepare(phy_drd->drv_data->n_clks, phy_drd->clks);
 
@@ -1203,6 +1227,8 @@ static int exynos850_usbdrd_phy_exit(struct phy *phy)
        if (ret)
                return ret;
 
+       guard(mutex)(&phy_drd->phy_mutex);
+
        /* Set PHY clock and control HS PHY */
        reg = readl(regs_base + EXYNOS850_DRD_UTMI);
        reg &= ~(UTMI_DP_PULLDOWN | UTMI_DM_PULLDOWN);
@@ -1698,6 +1724,10 @@ static int exynos5_usbdrd_phy_probe(struct platform_device *pdev)
                return -EINVAL;
        phy_drd->drv_data = drv_data;
 
+       ret = devm_mutex_init(dev, &phy_drd->phy_mutex);
+       if (ret)
+               return ret;
+
        if (of_property_present(dev->of_node, "reg-names")) {
                void __iomem *reg;