phy: phy-can-transceiver: Add support for setting mux

On some boards, for routing CAN signals from controller to transceiver,
muxes might need to be set. Therefore, add support for setting the mux by
reading the mux-states property from the device tree node.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Link: https://lore.kernel.org/r/20220408111316.21189-1-a-govindraju@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 82b63e60c5a226bded68c9fe4a0c469c4049e63f..300b0f2b5f8421e587f05ea1449ec358e013ad0f 100644 (file)
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -64,6 +64,7 @@ config USB_LGM_PHY
 config PHY_CAN_TRANSCEIVER
        tristate "CAN transceiver PHY"
        select GENERIC_PHY
+       select MULTIPLEXER
        help
          This option enables support for CAN transceivers as a PHY. This
          driver provides function for putting the transceivers in various

diff --git a/drivers/phy/phy-can-transceiver.c b/drivers/phy/phy-can-transceiver.c
index 6f3fe37dee0e85f3b0c87188ada8417a18f183c6..95c6dbb52da720bffcba85ff9ad037daed688009 100644 (file)
--- a/drivers/phy/phy-can-transceiver.c
+++ b/drivers/phy/phy-can-transceiver.c
@@ -10,6 +10,7 @@
 #include<linux/module.h>
 #include<linux/gpio.h>
 #include<linux/gpio/consumer.h>
+#include <linux/mux/consumer.h>
 
 struct can_transceiver_data {
        u32 flags;
@@ -21,13 +22,22 @@ struct can_transceiver_phy {
        struct phy *generic_phy;
        struct gpio_desc *standby_gpio;
        struct gpio_desc *enable_gpio;
+       struct mux_state *mux_state;
 };
 
 /* Power on function */
 static int can_transceiver_phy_power_on(struct phy *phy)
 {
        struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);
-
+       int ret;
+
+       if (can_transceiver_phy->mux_state) {
+               ret = mux_state_select(can_transceiver_phy->mux_state);
+               if (ret) {
+                       dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret);
+                       return ret;
+               }
+       }
        if (can_transceiver_phy->standby_gpio)
                gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0);
        if (can_transceiver_phy->enable_gpio)
@@ -45,6 +55,8 @@ static int can_transceiver_phy_power_off(struct phy *phy)
                gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1);
        if (can_transceiver_phy->enable_gpio)
                gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0);
+       if (can_transceiver_phy->mux_state)
+               mux_state_deselect(can_transceiver_phy->mux_state);
 
        return 0;
 }
@@ -95,6 +107,16 @@ static int can_transceiver_phy_probe(struct platform_device *pdev)
        match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node);
        drvdata = match->data;
 
+       if (of_property_read_bool(dev->of_node, "mux-states")) {
+               struct mux_state *mux_state;
+
+               mux_state = devm_mux_state_get(dev, NULL);
+               if (IS_ERR(mux_state))
+                       return dev_err_probe(&pdev->dev, PTR_ERR(mux_state),
+                                            "failed to get mux\n");
+               can_transceiver_phy->mux_state = mux_state;
+       }
+
        phy = devm_phy_create(dev, dev->of_node,
                              &can_transceiver_phy_ops);
        if (IS_ERR(phy)) {