i2c: omap: split out [XR]DR and [XR]RDY

While they do pretty much the same thing, there
are a few peculiarities. Specially WRT erratas,
it's best to split those out and re-factor the
read/write loop to another function which both
cases call.

This last part will be done on another patch.

While at that, also avoid an unncessary register
read since dev->fifo_len will always contain the
correct amount of data to be transferred.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

1 files changed, 92 insertions, 34 deletions

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index f24eae9f7f1e..815577b1c89f 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -801,36 +801,62 @@ complete:
                         return IRQ_HANDLED;
                 }
 
-                if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
+                if (stat & OMAP_I2C_STAT_RDR) {
                         u8 num_bytes = 1;
 
+                        if (dev->fifo_size)
+                                num_bytes = dev->buf_len;
+
+                        while (num_bytes--) {
+                                if (!dev->buf_len) {
+                                        dev_err(dev->dev,
+                                                        "RDR IRQ while no data"
+                                                        " requested\n");
+                                        break;
+                                }
+
+                                w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+                                *dev->buf++ = w;
+                                dev->buf_len--;
+
+                                /*
+                                 * Data reg in 2430, omap3 and
+                                 * omap4 is 8 bit wide
+                                 */
+                                if (dev->flags &
+                                                OMAP_I2C_FLAG_16BIT_DATA_REG) {
+                                        if (dev->buf_len) {
+                                                *dev->buf++ = w >> 8;
+                                                dev->buf_len--;
+                                        }
+                                }
+                        }
+
                         if (dev->errata & I2C_OMAP_ERRATA_I207)
                                 i2c_omap_errata_i207(dev, stat);
 
-                        if (dev->fifo_size) {
-                                if (stat & OMAP_I2C_STAT_RRDY)
-                                        num_bytes = dev->fifo_size;
-                                else    /* read RXSTAT on RDR interrupt */
-                                        num_bytes = (omap_i2c_read_reg(dev,
-                                                        OMAP_I2C_BUFSTAT_REG)
-                                                        >> 8) & 0x3F;
-                        }
+                        omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+                        continue;
+                }
+
+                if (stat & OMAP_I2C_STAT_RRDY) {
+                        u8 num_bytes = 1;
+
+                        if (dev->fifo_size)
+                                num_bytes = dev->fifo_size;
+
                         while (num_bytes--) {
                                 if (!dev->buf_len) {
-                                        if (stat & OMAP_I2C_STAT_RRDY)
-                                                dev_err(dev->dev,
+                                        dev_err(dev->dev,
                                                         "RRDY IRQ while no data"
-                                                                " requested\n");
-                                        if (stat & OMAP_I2C_STAT_RDR)
-                                                dev_err(dev->dev,
-                                                        "RDR IRQ while no data"
-                                                                " requested\n");
+                                                        " requested\n");
                                         break;
                                 }
 
                                 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
                                 *dev->buf++ = w;
                                 dev->buf_len--;
+
                                 /*
                                  * Data reg in 2430, omap3 and
                                  * omap4 is 8 bit wide
@@ -843,36 +869,68 @@ complete:
                                         }
                                 }
                         }
-                        omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
-                                                OMAP_I2C_STAT_RDR));
+
+                        omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
                         continue;
                 }
 
-                if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
+                if (stat & OMAP_I2C_STAT_XDR) {
                         u8 num_bytes = 1;
-                        if (dev->fifo_size) {
-                                if (stat & OMAP_I2C_STAT_XRDY)
-                                        num_bytes = dev->fifo_size;
-                                else    /* read TXSTAT on XDR interrupt */
-                                        num_bytes = omap_i2c_read_reg(dev,
-                                                        OMAP_I2C_BUFSTAT_REG)
-                                                        & 0x3F;
+
+                        if (dev->fifo_size)
+                                num_bytes = dev->buf_len;
+
+                        while (num_bytes--) {
+                                if (!dev->buf_len) {
+                                        dev_err(dev->dev,
+                                                        "XDR IRQ while no "
+                                                        "data to send\n");
+                                        break;
+                                }
+
+                                w = *dev->buf++;
+                                dev->buf_len--;
+
+                                /*
+                                 * Data reg in 2430, omap3 and
+                                 * omap4 is 8 bit wide
+                                 */
+                                if (dev->flags &
+                                                OMAP_I2C_FLAG_16BIT_DATA_REG) {
+                                        if (dev->buf_len) {
+                                                w |= *dev->buf++ << 8;
+                                                dev->buf_len--;
+                                        }
+                                }
+
+                                if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
+                                    errata_omap3_i462(dev, &stat, &err))
+                                        goto complete;
+
+                                omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
                         }
+
+                        omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
+                        continue;
+                }
+
+                if (stat & OMAP_I2C_STAT_XRDY) {
+                        u8 num_bytes = 1;
+
+                        if (dev->fifo_size)
+                                num_bytes = dev->fifo_size;
+
                         while (num_bytes--) {
                                 if (!dev->buf_len) {
-                                        if (stat & OMAP_I2C_STAT_XRDY)
-                                                dev_err(dev->dev,
+                                        dev_err(dev->dev,
                                                         "XRDY IRQ while no "
                                                         "data to send\n");
-                                        if (stat & OMAP_I2C_STAT_XDR)
-                                                dev_err(dev->dev,
-                                                        "XDR IRQ while no "
-                                                        "data to send\n");
                                         break;
                                 }
 
                                 w = *dev->buf++;
                                 dev->buf_len--;
+
                                 /*
                                  * Data reg in 2430, omap3 and
                                  * omap4 is 8 bit wide
@@ -891,8 +949,8 @@ complete:
 
                                 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
                         }
-                        omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
-                                                OMAP_I2C_STAT_XDR));
+
+                        omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
                         continue;
                 }