Merge git://git.denx.de/u-boot-rockchip

[u-boot] / drivers / serial / serial_bcm283x_mu.c

diff --git a/drivers/serial/serial_bcm283x_mu.c b/drivers/serial/serial_bcm283x_mu.c
index fc36bc0e85d67d808b166521d67149c5a802a7d9..40029fadbcb4b7751078725be18d2ad502aac41c 100644 (file)
--- a/drivers/serial/serial_bcm283x_mu.c
+++ b/drivers/serial/serial_bcm283x_mu.c
@@ -19,11 +19,12 @@
 #include <dm.h>
 #include <errno.h>
 #include <watchdog.h>
+#include <asm/gpio.h>
 #include <asm/io.h>
 #include <serial.h>
 #include <dm/platform_data/serial_bcm283x_mu.h>
+#include <dm/pinctrl.h>
 #include <linux/compiler.h>
-#include <fdtdec.h>
 
 struct bcm283x_mu_regs {
        u32 io;
@@ -112,13 +113,15 @@ static int bcm283x_mu_serial_pending(struct udevice *dev, bool input)
 {
        struct bcm283x_mu_priv *priv = dev_get_priv(dev);
        struct bcm283x_mu_regs *regs = priv->regs;
-       unsigned int lsr = readl(&regs->lsr);
+       unsigned int lsr;
+
+       lsr = readl(&regs->lsr);
 
        if (input) {
                WATCHDOG_RESET();
-               return lsr & BCM283X_MU_LSR_RX_READY;
+               return (lsr & BCM283X_MU_LSR_RX_READY) ? 1 : 0;
        } else {
-               return !(lsr & BCM283X_MU_LSR_TX_IDLE);
+               return (lsr & BCM283X_MU_LSR_TX_IDLE) ? 0 : 1;
        }
 }
 
@@ -129,9 +132,65 @@ static const struct dm_serial_ops bcm283x_mu_serial_ops = {
        .setbrg = bcm283x_mu_serial_setbrg,
 };
 
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+static const struct udevice_id bcm283x_mu_serial_id[] = {
+       {.compatible = "brcm,bcm2835-aux-uart"},
+       {}
+};
+
+/*
+ * Check if this serial device is muxed
+ *
+ * The serial device will only work properly if it has been muxed to the serial
+ * pins by firmware. Check whether that happened here.
+ *
+ * @return true if serial device is muxed, false if not
+ */
+static bool bcm283x_is_serial_muxed(void)
+{
+       int serial_gpio = 15;
+       struct udevice *dev;
+
+       if (uclass_first_device(UCLASS_PINCTRL, &dev) || !dev)
+               return false;
+
+       if (pinctrl_get_gpio_mux(dev, 0, serial_gpio) != BCM2835_GPIO_ALT5)
+               return false;
+
+       return true;
+}
+
+static int bcm283x_mu_serial_ofdata_to_platdata(struct udevice *dev)
+{
+       struct bcm283x_mu_serial_platdata *plat = dev_get_platdata(dev);
+       fdt_addr_t addr;
+
+       /* Don't spawn the device if it's not muxed */
+       if (!bcm283x_is_serial_muxed())
+               return -ENODEV;
+
+       addr = devfdt_get_addr(dev);
+       if (addr == FDT_ADDR_T_NONE)
+               return -EINVAL;
+
+       plat->base = addr;
+       plat->clock = dev_read_u32_default(dev, "clock", 1);
+
+       /*
+        * TODO: Reinitialization doesn't always work for now, just skip
+        *       init always - we know we're already initialized
+        */
+       plat->skip_init = true;
+
+       return 0;
+}
+#endif
+
 U_BOOT_DRIVER(serial_bcm283x_mu) = {
        .name = "serial_bcm283x_mu",
        .id = UCLASS_SERIAL,
+       .of_match = of_match_ptr(bcm283x_mu_serial_id),
+       .ofdata_to_platdata = of_match_ptr(bcm283x_mu_serial_ofdata_to_platdata),
        .platdata_auto_alloc_size = sizeof(struct bcm283x_mu_serial_platdata),
        .probe = bcm283x_mu_serial_probe,
        .ops = &bcm283x_mu_serial_ops,