From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> We may use special helper macro to poll IO till condition or timeout occurs. Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200217161038.25009-1-andriy.shevchenko@xxxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- drivers/net/can/spi/mcp251x.c | 64 ++++++++++++++++++----------------- 1 file changed, 33 insertions(+), 31 deletions(-) diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c index 4b113f61e39d..3bf57bc9b3ff 100644 --- 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) -- 2.28.0
