I2C: Clean-up i2c-omap

Clean-up i2c-omap

Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 0f7cbe8f5cefc7e11d239efd55d4f913cad9efa5..a8c8831313dc3658e5411509648fb992a25b515d 100644 (file)
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -9,8 +9,9 @@
  * Additional contributions by:
  *     Tony Lindgren <tony@atomide.com>
  *     Imre Deak <imre.deak@nokia.com>
- *     Juha Yrjölä <juha.yrjola@nokia.com>
+ *     Juha Yrjölä <juha.yrjola@solidboot.com>
  *     Syed Khasim <x0khasim@ti.com>
+ *     Nishant Menon <nm@ti.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -35,8 +36,7 @@
 #include <linux/completion.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
-
-#include <asm/io.h>
+#include <linux/io.h>
 
 /* Hack to enable zero length transfers and smbus quick until clean fix
    is available */
@@ -64,8 +64,8 @@
 #define OMAP_I2C_BUFSTAT_REG           0x40
 
 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
-#define OMAP_I2C_IE_XDR                (1 << 14)       /* TX Buffer draining int enable */
-#define OMAP_I2C_IE_RDR                (1 << 13)       /* RX Buffer draining int enable */
+#define OMAP_I2C_IE_XDR                (1 << 14)       /* TX Buffer drain int enable */
+#define OMAP_I2C_IE_RDR                (1 << 13)       /* RX Buffer drain int enable */
 #define OMAP_I2C_IE_XRDY       (1 << 4)        /* TX data ready int enable */
 #define OMAP_I2C_IE_RRDY       (1 << 3)        /* RX data ready int enable */
 #define OMAP_I2C_IE_ARDY       (1 << 2)        /* Access ready int enable */
@@ -221,7 +221,7 @@ static void omap_i2c_idle(struct omap_i2c_dev *dev)
        dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
        omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
        if (dev->rev1)
-               iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
+               iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
        else
                omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
        /*
@@ -439,18 +439,24 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 
        omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 
+       /*
+        * Don't write stt and stp together on some hardware
+        */
        if (dev->b_hw && stop) {
                unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
+               u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
+               while (con & OMAP_I2C_CON_STT) {
+                       con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 
-               /* H/w behavior: dont write stt and stp together.. */
-               while (omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) & OMAP_I2C_CON_STT) {
                        /* Let the user know if i2c is in a bad state */
-                       if (time_after (jiffies, delay)) {
+                       if (time_after(jiffies, delay)) {
                                dev_err(dev->dev, "controller timed out "
                                "waiting for start condition to finish\n");
                                return -ETIMEDOUT;
                        }
+                       cpu_relax();
                }
+
                w |= OMAP_I2C_CON_STP;
                w &= ~OMAP_I2C_CON_STT;
                omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
@@ -503,7 +509,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 
        omap_i2c_unidle(dev);
 
-       if ((r = omap_i2c_wait_for_bb(dev)) < 0)
+       r = omap_i2c_wait_for_bb(dev);
+       if (r < 0)
                goto out;
 
        for (i = 0; i < num; i++) {
@@ -640,8 +647,11 @@ omap_i2c_isr(int this_irq, void *dev_id)
                if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
                        u8 num_bytes = 1;
                        if (dev->fifo_size) {
-                               num_bytes = (stat & OMAP_I2C_STAT_RRDY) ? dev->fifo_size :
-                                               omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG);
+                               if (stat & OMAP_I2C_STAT_RRDY)
+                                       num_bytes = dev->fifo_size;
+                               else
+                                       num_bytes = omap_i2c_read_reg(dev,
+                                                       OMAP_I2C_BUFSTAT_REG);
                        }
                        while (num_bytes) {
                                num_bytes--;
@@ -659,22 +669,28 @@ omap_i2c_isr(int this_irq, void *dev_id)
                                        }
                                } else {
                                        if (stat & OMAP_I2C_STAT_RRDY)
-                                               dev_err(dev->dev, "RRDY IRQ while no data "
-                                                               "requested\n");
+                                               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");
+                                               dev_err(dev->dev,
+                                                       "RDR IRQ while no data"
+                                                               " requested\n");
                                        break;
                                }
                        }
-                       omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
+                       omap_i2c_ack_stat(dev,
+                               stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
                        continue;
                }
                if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
                        u8 num_bytes = 1;
                        if (dev->fifo_size) {
-                               num_bytes = (stat & OMAP_I2C_STAT_XRDY) ? dev->fifo_size :
-                                               omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG);
+                               if (stat & OMAP_I2C_STAT_XRDY)
+                                       num_bytes = dev->fifo_size;
+                               else
+                                       num_bytes = omap_i2c_read_reg(dev,
+                                                       OMAP_I2C_BUFSTAT_REG);
                        }
                        while (num_bytes) {
                                num_bytes--;
@@ -692,16 +708,19 @@ omap_i2c_isr(int this_irq, void *dev_id)
                                        }
                                } else {
                                        if (stat & OMAP_I2C_STAT_XRDY)
-                                               dev_err(dev->dev, "XRDY IRQ while no "
-                                                               "data to send\n");
+                                               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");
+                                               dev_err(dev->dev,
+                                                       "XDR IRQ while no "
+                                                       "data to send\n");
                                        break;
                                }
                                omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
                        }
-                       omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
+                       omap_i2c_ack_stat(dev,
+                               stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
                        continue;
                }
                if (stat & OMAP_I2C_STAT_ROVR) {
@@ -772,7 +791,8 @@ omap_i2c_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, dev);
 
-       if ((r = omap_i2c_get_clocks(dev)) != 0)
+       r = omap_i2c_get_clocks(dev);
+       if (r != 0)
                goto err_iounmap;
 
        omap_i2c_unidle(dev);
@@ -781,13 +801,16 @@ omap_i2c_probe(struct platform_device *pdev)
                dev->rev1 = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) < 0x20;
 
        if (cpu_is_omap2430() || cpu_is_omap34xx()) {
+               u16 s;
+
                /* Set up the fifo size - Get total size */
-               dev->fifo_size = 0x8 <<
-                       ((omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3);
+               s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
+               dev->fifo_size = 0x8 << s;
+
                /*
-                * Set up notification threshold as half the total available size
-                * This is to ensure that we can handle the status on int call back
-                * latencies
+                * Set up notification threshold as half the total available
+                * size. This is to ensure that we can handle the status on int
+                * call back latencies.
                 */
                dev->fifo_size = (dev->fifo_size / 2);
                dev->b_hw = 1; /* Enable hardware fixes */