can: mcp251x: Use readx_poll_timeout() helper

We may use special helper macro to poll IO till condition or timeout occurs.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217161038.25009-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
index 4b113f6..3bf57bc 100644 (file)
--- a/drivers/net/can/spi/mcp251x.c
+++ b/drivers/net/can/spi/mcp251x.c
@@ -32,6 +32,7 @@
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
@@ -376,6 +377,15 @@ static void mcp251x_write_bits(struct spi_device *spi, u8 reg,
        mcp251x_spi_trans(spi, 4);
 }
 
+static u8 mcp251x_read_stat(struct spi_device *spi)
+{
+       return mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK;
+}
+
+#define mcp251x_read_stat_poll_timeout(addr, val, cond, delay_us, timeout_us) \
+       readx_poll_timeout(mcp251x_read_stat, addr, val, cond, \
+                          delay_us, timeout_us)
+
 #ifdef CONFIG_GPIOLIB
 enum {
        MCP251X_GPIO_TX0RTS = 0,                /* inputs */
@@ -709,7 +719,8 @@ static void mcp251x_hw_sleep(struct spi_device *spi)
 /* May only be called when device is sleeping! */
 static int mcp251x_hw_wake(struct spi_device *spi)
 {
-       unsigned long timeout;
+       u8 value;
+       int ret;
 
        /* Force wakeup interrupt to wake device, but don't execute IST */
        disable_irq(spi->irq);
@@ -722,14 +733,12 @@ static int mcp251x_hw_wake(struct spi_device *spi)
        mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_CONF);
 
        /* Wait for the device to enter config mode */
-       timeout = jiffies + HZ;
-       while ((mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) !=
-                       CANCTRL_REQOP_CONF) {
-               schedule();
-               if (time_after(jiffies, timeout)) {
-                       dev_err(&spi->dev, "MCP251x didn't enter in config mode\n");
-                       return -EBUSY;
-               }
+       ret = mcp251x_read_stat_poll_timeout(spi, value, value == CANCTRL_REQOP_CONF,
+                                            MCP251X_OST_DELAY_MS * 1000,
+                                            USEC_PER_SEC);
+       if (ret) {
+               dev_err(&spi->dev, "MCP251x didn't enter in config mode\n");
+               return ret;
        }
 
        /* Disable and clear pending interrupts */
@@ -784,7 +793,8 @@ static int mcp251x_do_set_mode(struct net_device *net, enum can_mode mode)
 static int mcp251x_set_normal_mode(struct spi_device *spi)
 {
        struct mcp251x_priv *priv = spi_get_drvdata(spi);
-       unsigned long timeout;
+       u8 value;
+       int ret;
 
        /* Enable interrupts */
        mcp251x_write_reg(spi, CANINTE,
@@ -802,13 +812,12 @@ static int mcp251x_set_normal_mode(struct spi_device *spi)
                mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_NORMAL);
 
                /* Wait for the device to enter normal mode */
-               timeout = jiffies + HZ;
-               while (mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) {
-                       schedule();
-                       if (time_after(jiffies, timeout)) {
-                               dev_err(&spi->dev, "MCP251x didn't enter in normal mode\n");
-                               return -EBUSY;
-                       }
+               ret = mcp251x_read_stat_poll_timeout(spi, value, value == 0,
+                                                    MCP251X_OST_DELAY_MS * 1000,
+                                                    USEC_PER_SEC);
+               if (ret) {
+                       dev_err(&spi->dev, "MCP251x didn't enter in normal mode\n");
+                       return ret;
                }
        }
        priv->can.state = CAN_STATE_ERROR_ACTIVE;
@@ -852,7 +861,7 @@ static int mcp251x_setup(struct net_device *net, struct spi_device *spi)
 static int mcp251x_hw_reset(struct spi_device *spi)
 {
        struct mcp251x_priv *priv = spi_get_drvdata(spi);
-       unsigned long timeout;
+       u8 value;
        int ret;
 
        /* Wait for oscillator startup timer after power up */
@@ -867,19 +876,12 @@ static int mcp251x_hw_reset(struct spi_device *spi)
        mdelay(MCP251X_OST_DELAY_MS);
 
        /* Wait for reset to finish */
-       timeout = jiffies + HZ;
-       while ((mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) !=
-              CANCTRL_REQOP_CONF) {
-               usleep_range(MCP251X_OST_DELAY_MS * 1000,
-                            MCP251X_OST_DELAY_MS * 1000 * 2);
-
-               if (time_after(jiffies, timeout)) {
-                       dev_err(&spi->dev,
-                               "MCP251x didn't enter in conf mode after reset\n");
-                       return -EBUSY;
-               }
-       }
-       return 0;
+       ret = mcp251x_read_stat_poll_timeout(spi, value, value == CANCTRL_REQOP_CONF,
+                                            MCP251X_OST_DELAY_MS * 1000,
+                                            USEC_PER_SEC);
+       if (ret)
+               dev_err(&spi->dev, "MCP251x didn't enter in conf mode after reset\n");
+       return ret;
 }
 
 static int mcp251x_hw_probe(struct spi_device *spi)