These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / tty / serial / mxs-auart.c

diff --git a/kernel/drivers/tty/serial/mxs-auart.c b/kernel/drivers/tty/serial/mxs-auart.c
index f7e5825..cd0414b 100644 (file)
--- a/kernel/drivers/tty/serial/mxs-auart.c
+++ b/kernel/drivers/tty/serial/mxs-auart.c
@@ -100,6 +100,8 @@
 #define AUART_CTRL2_TXE                                (1 << 8)
 #define AUART_CTRL2_UARTEN                     (1 << 0)
 
+#define AUART_LINECTRL_BAUD_DIV_MAX            0x003fffc0
+#define AUART_LINECTRL_BAUD_DIV_MIN            0x000000ec
 #define AUART_LINECTRL_BAUD_DIVINT_SHIFT       16
 #define AUART_LINECTRL_BAUD_DIVINT_MASK                0xffff0000
 #define AUART_LINECTRL_BAUD_DIVINT(v)          (((v) & 0xffff) << 16)
@@ -169,7 +171,7 @@ struct mxs_auart_port {
        bool                    ms_irq_enabled;
 };
 
-static struct platform_device_id mxs_auart_devtype[] = {
+static const struct platform_device_id mxs_auart_devtype[] = {
        { .name = "mxs-auart-imx23", .driver_data = IMX23_AUART },
        { .name = "mxs-auart-imx28", .driver_data = IMX28_AUART },
        { /* sentinel */ }
@@ -659,7 +661,7 @@ static void mxs_auart_settermios(struct uart_port *u,
 {
        struct mxs_auart_port *s = to_auart_port(u);
        u32 bm, ctrl, ctrl2, div;
-       unsigned int cflag, baud;
+       unsigned int cflag, baud, baud_min, baud_max;
 
        cflag = termios->c_cflag;
 
@@ -752,7 +754,9 @@ static void mxs_auart_settermios(struct uart_port *u,
        }
 
        /* set baud rate */
-       baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk);
+       baud_min = DIV_ROUND_UP(u->uartclk * 32, AUART_LINECTRL_BAUD_DIV_MAX);
+       baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN;
+       baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max);
        div = u->uartclk * 32 / baud;
        ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F);
        ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6);
@@ -842,7 +846,7 @@ static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
        return IRQ_HANDLED;
 }
 
-static void mxs_auart_reset(struct uart_port *u)
+static void mxs_auart_reset_deassert(struct uart_port *u)
 {
        int i;
        unsigned int reg;
@@ -858,6 +862,30 @@ static void mxs_auart_reset(struct uart_port *u)
        writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
 }
 
+static void mxs_auart_reset_assert(struct uart_port *u)
+{
+       int i;
+       u32 reg;
+
+       reg = readl(u->membase + AUART_CTRL0);
+       /* if already in reset state, keep it untouched */
+       if (reg & AUART_CTRL0_SFTRST)
+               return;
+
+       writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
+       writel(AUART_CTRL0_SFTRST, u->membase + AUART_CTRL0_SET);
+
+       for (i = 0; i < 1000; i++) {
+               reg = readl(u->membase + AUART_CTRL0);
+               /* reset is finished when the clock is gated */
+               if (reg & AUART_CTRL0_CLKGATE)
+                       return;
+               udelay(10);
+       }
+
+       dev_err(u->dev, "Failed to reset the unit.");
+}
+
 static int mxs_auart_startup(struct uart_port *u)
 {
        int ret;
@@ -867,7 +895,13 @@ static int mxs_auart_startup(struct uart_port *u)
        if (ret)
                return ret;
 
-       writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
+       if (uart_console(u)) {
+               writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR);
+       } else {
+               /* reset the unit to a well known state */
+               mxs_auart_reset_assert(u);
+               mxs_auart_reset_deassert(u);
+       }
 
        writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_SET);
 
@@ -899,12 +933,14 @@ static void mxs_auart_shutdown(struct uart_port *u)
        if (auart_dma_enabled(s))
                mxs_auart_dma_exit(s);
 
-       writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR);
-
-       writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
-                       u->membase + AUART_INTR_CLR);
-
-       writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
+       if (uart_console(u)) {
+               writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR);
+               writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN,
+                               u->membase + AUART_INTR_CLR);
+               writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET);
+       } else {
+               mxs_auart_reset_assert(u);
+       }
 
        clk_disable_unprepare(s->clk);
 }
@@ -1160,7 +1196,7 @@ static int mxs_auart_init_gpios(struct mxs_auart_port *s, struct device *dev)
        enum mctrl_gpio_idx i;
        struct gpio_desc *gpiod;
 
-       s->gpios = mctrl_gpio_init(dev, 0);
+       s->gpios = mctrl_gpio_init_noauto(dev, 0);
        if (IS_ERR(s->gpios))
                return PTR_ERR(s->gpios);
 
@@ -1291,7 +1327,7 @@ static int mxs_auart_probe(struct platform_device *pdev)
 
        auart_port[s->port.line] = s;
 
-       mxs_auart_reset(&s->port);
+       mxs_auart_reset_deassert(&s->port);
 
        ret = uart_add_one_port(&auart_driver, &s->port);
        if (ret)