Merge branch 'master' of git://git.denx.de/u-boot-i2c

[oweals/u-boot.git] / drivers / i2c / i2c-cdns.c

diff --git a/drivers/i2c/i2c-cdns.c b/drivers/i2c/i2c-cdns.c
index f2c4b2073c48aa552c3679dd3902c20ca5ca7db7..2c0301ad083a0dbc4b7146f9e3a3c640f314960b 100644 (file)
--- a/drivers/i2c/i2c-cdns.c
+++ b/drivers/i2c/i2c-cdns.c
@@ -64,12 +64,24 @@ struct cdns_i2c_regs {
 #define CDNS_I2C_INTERRUPT_RXUNF       0x00000080
 #define CDNS_I2C_INTERRUPT_ARBLOST     0x00000200
 
+#define CDNS_I2C_INTERRUPTS_MASK       (CDNS_I2C_INTERRUPT_COMP | \
+                                       CDNS_I2C_INTERRUPT_DATA | \
+                                       CDNS_I2C_INTERRUPT_NACK | \
+                                       CDNS_I2C_INTERRUPT_TO | \
+                                       CDNS_I2C_INTERRUPT_SLVRDY | \
+                                       CDNS_I2C_INTERRUPT_RXOVF | \
+                                       CDNS_I2C_INTERRUPT_TXOVF | \
+                                       CDNS_I2C_INTERRUPT_RXUNF | \
+                                       CDNS_I2C_INTERRUPT_ARBLOST)
+
 #define CDNS_I2C_FIFO_DEPTH            16
 #define CDNS_I2C_TRANSFER_SIZE_MAX     255 /* Controller transfer limit */
 #define CDNS_I2C_TRANSFER_SIZE         (CDNS_I2C_TRANSFER_SIZE_MAX - 3)
 
 #define CDNS_I2C_BROKEN_HOLD_BIT       BIT(0)
 
+#define CDNS_I2C_ARB_LOST_MAX_RETRIES  10
+
 #ifdef DEBUG
 static void cdns_i2c_debug_status(struct cdns_i2c_regs *cdns_i2c)
 {
@@ -224,11 +236,17 @@ static int cdns_i2c_set_bus_speed(struct udevice *dev, unsigned int speed)
        return 0;
 }
 
+static inline u32 is_arbitration_lost(struct cdns_i2c_regs *regs)
+{
+       return (readl(&regs->interrupt_status) & CDNS_I2C_INTERRUPT_ARBLOST);
+}
+
 static int cdns_i2c_write_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
                               u32 len)
 {
        u8 *cur_data = data;
        struct cdns_i2c_regs *regs = i2c_bus->regs;
+       u32 ret;
 
        /* Set the controller in Master transmit mode and clear FIFO */
        setbits_le32(&regs->control, CDNS_I2C_CONTROL_CLR_FIFO);
@@ -241,29 +259,42 @@ static int cdns_i2c_write_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
                setbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
 
        /* Clear the interrupts in status register */
-       writel(0xFF, &regs->interrupt_status);
+       writel(CDNS_I2C_INTERRUPTS_MASK, &regs->interrupt_status);
 
        writel(addr, &regs->address);
 
-       while (len--) {
+       while (len-- && !is_arbitration_lost(regs)) {
                writel(*(cur_data++), &regs->data);
                if (readl(&regs->transfer_size) == CDNS_I2C_FIFO_DEPTH) {
-                       if (!cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP)) {
-                               /* Release the bus */
-                               clrbits_le32(&regs->control,
-                                            CDNS_I2C_CONTROL_HOLD);
-                               return -ETIMEDOUT;
-                       }
+                       ret = cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP |
+                                           CDNS_I2C_INTERRUPT_ARBLOST);
+                       if (ret & CDNS_I2C_INTERRUPT_ARBLOST)
+                               return -EAGAIN;
+                       if (ret & CDNS_I2C_INTERRUPT_COMP)
+                               continue;
+                       /* Release the bus */
+                       clrbits_le32(&regs->control,
+                                    CDNS_I2C_CONTROL_HOLD);
+                       return -ETIMEDOUT;
                }
        }
 
+       if (len && is_arbitration_lost(regs))
+               return -EAGAIN;
+
        /* All done... release the bus */
        if (!i2c_bus->hold_flag)
                clrbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
 
        /* Wait for the address and data to be sent */
-       if (!cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP))
+       ret = cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP |
+                           CDNS_I2C_INTERRUPT_ARBLOST);
+       if (!(ret & (CDNS_I2C_INTERRUPT_ARBLOST |
+                    CDNS_I2C_INTERRUPT_COMP)))
                return -ETIMEDOUT;
+       if (ret & CDNS_I2C_INTERRUPT_ARBLOST)
+               return -EAGAIN;
+
        return 0;
 }
 
@@ -277,12 +308,9 @@ static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
 {
        u8 *cur_data = data;
        struct cdns_i2c_regs *regs = i2c_bus->regs;
-       int curr_recv_count;
+       u32 curr_recv_count;
        int updatetx, hold_quirk;
-
-       /* Check the hardware can handle the requested bytes */
-       if ((recv_count < 0))
-               return -EINVAL;
+       u32 ret;
 
        curr_recv_count = recv_count;
 
@@ -307,7 +335,7 @@ static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
 
        hold_quirk = (i2c_bus->quirks & CDNS_I2C_BROKEN_HOLD_BIT) && updatetx;
 
-       while (recv_count) {
+       while (recv_count && !is_arbitration_lost(regs)) {
                while (readl(&regs->status) & CDNS_I2C_STATUS_RXDV) {
                        if (recv_count < CDNS_I2C_FIFO_DEPTH &&
                            !i2c_bus->hold_flag) {
@@ -356,8 +384,13 @@ static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
        }
 
        /* Wait for the address and data to be sent */
-       if (!cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP))
+       ret = cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP |
+                           CDNS_I2C_INTERRUPT_ARBLOST);
+       if (!(ret & (CDNS_I2C_INTERRUPT_ARBLOST |
+                    CDNS_I2C_INTERRUPT_COMP)))
                return -ETIMEDOUT;
+       if (ret & CDNS_I2C_INTERRUPT_ARBLOST)
+               return -EAGAIN;
 
        return 0;
 }
@@ -366,8 +399,11 @@ static int cdns_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
                         int nmsgs)
 {
        struct i2c_cdns_bus *i2c_bus = dev_get_priv(dev);
-       int ret, count;
+       int ret = 0;
+       int count;
        bool hold_quirk;
+       struct i2c_msg *message = msg;
+       int num_msgs = nmsgs;
 
        hold_quirk = !!(i2c_bus->quirks & CDNS_I2C_BROKEN_HOLD_BIT);
 
@@ -393,7 +429,8 @@ static int cdns_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
        }
 
        debug("i2c_xfer: %d messages\n", nmsgs);
-       for (; nmsgs > 0; nmsgs--, msg++) {
+       for (u8 retry = 0; retry < CDNS_I2C_ARB_LOST_MAX_RETRIES &&
+            nmsgs > 0; nmsgs--, msg++) {
                debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
                if (msg->flags & I2C_M_RD) {
                        ret = cdns_i2c_read_data(i2c_bus, msg->addr, msg->buf,
@@ -402,13 +439,22 @@ static int cdns_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
                        ret = cdns_i2c_write_data(i2c_bus, msg->addr, msg->buf,
                                                  msg->len);
                }
+               if (ret == -EAGAIN) {
+                       msg = message;
+                       nmsgs = num_msgs;
+                       retry++;
+                       printf("%s,arbitration lost, retrying:%d\n", __func__,
+                              retry);
+                       continue;
+               }
+
                if (ret) {
                        debug("i2c_write: error sending\n");
                        return -EREMOTEIO;
                }
        }
 
-       return 0;
+       return ret;
 }
 
 static int cdns_i2c_ofdata_to_platdata(struct udevice *dev)
@@ -419,7 +465,7 @@ static int cdns_i2c_ofdata_to_platdata(struct udevice *dev)
        struct clk clk;
        int ret;
 
-       i2c_bus->regs = (struct cdns_i2c_regs *)devfdt_get_addr(dev);
+       i2c_bus->regs = (struct cdns_i2c_regs *)dev_read_addr(dev);
        if (!i2c_bus->regs)
                return -ENOMEM;