]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/i2c/busses/i2c-omap.c
i2c: i2c-omap: Fix BUFSTAT_REG reading
[linux-2.6-omap-h63xx.git] / drivers / i2c / busses / i2c-omap.c
index a9996063483e9c269c8a2e45e8e737ed0f923e33..71b37ed4b72c1b246b600390cb3db94ed01b76ca 100644 (file)
 #include <linux/clk.h>
 #include <linux/io.h>
 
+/* I2C controller revisions */
+#define OMAP_I2C_REV_2                 0x20
+
+/* I2C controller revisions present on specific hardware */
+#define OMAP_I2C_REV_ON_2430           0x36
+#define OMAP_I2C_REV_ON_3430           0x3C
+
 /* timeout waiting for the controller to respond */
 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
 
@@ -45,6 +52,8 @@
 #define OMAP_I2C_IE_REG                        0x04
 #define OMAP_I2C_STAT_REG              0x08
 #define OMAP_I2C_IV_REG                        0x0c
+/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
+#define OMAP_I2C_WE_REG                        0x0c
 #define OMAP_I2C_SYSS_REG              0x10
 #define OMAP_I2C_BUF_REG               0x14
 #define OMAP_I2C_CNT_REG               0x18
 #define OMAP_I2C_STAT_NACK     (1 << 1)        /* No ack interrupt enable */
 #define OMAP_I2C_STAT_AL       (1 << 0)        /* Arbitration lost int ena */
 
+/* I2C WE wakeup enable register */
+#define OMAP_I2C_WE_XDR_WE     (1 << 14)       /* TX drain wakup */
+#define OMAP_I2C_WE_RDR_WE     (1 << 13)       /* RX drain wakeup */
+#define OMAP_I2C_WE_AAS_WE     (1 << 9)        /* Address as slave wakeup*/
+#define OMAP_I2C_WE_BF_WE      (1 << 8)        /* Bus free wakeup */
+#define OMAP_I2C_WE_STC_WE     (1 << 6)        /* Start condition wakeup */
+#define OMAP_I2C_WE_GC_WE      (1 << 5)        /* General call wakeup */
+#define OMAP_I2C_WE_DRDY_WE    (1 << 3)        /* TX/RX data ready wakeup */
+#define OMAP_I2C_WE_ARDY_WE    (1 << 2)        /* Reg access ready wakeup */
+#define OMAP_I2C_WE_NACK_WE    (1 << 1)        /* No acknowledgment wakeup */
+#define OMAP_I2C_WE_AL_WE      (1 << 0)        /* Arbitration lost wakeup */
+
+#define OMAP_I2C_WE_ALL                (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
+                               OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
+                               OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
+                               OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
+                               OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
+
 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
 #define OMAP_I2C_BUF_RDMA_EN   (1 << 15)       /* RX DMA channel enable */
 #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14)       /* RX FIFO Clear */
 #define OMAP_I2C_SYSTEST_SDA_O         (1 << 0)        /* SDA line drive out */
 #endif
 
-/* I2C System Status register (OMAP_I2C_SYSS): */
-#define OMAP_I2C_SYSS_RDONE            (1 << 0)        /* Reset Done */
+/* OCP_SYSSTATUS bit definitions */
+#define SYSS_RESETDONE_MASK            (1 << 0)
+
+/* OCP_SYSCONFIG bit definitions */
+#define SYSC_CLOCKACTIVITY_MASK                (0x3 << 8)
+#define SYSC_SIDLEMODE_MASK            (0x3 << 3)
+#define SYSC_ENAWAKEUP_MASK            (1 << 2)
+#define SYSC_SOFTRESET_MASK            (1 << 1)
+#define SYSC_AUTOIDLE_MASK             (1 << 0)
+
+#define SYSC_IDLEMODE_SMART            0x2
+#define SYSC_CLOCKACTIVITY_FCLK                0x2
 
-/* I2C System Configuration Register (OMAP_I2C_SYSC): */
-#define OMAP_I2C_SYSC_SRST             (1 << 1)        /* Soft Reset */
 
 struct omap_i2c_dev {
        struct device           *dev;
@@ -139,7 +174,7 @@ struct omap_i2c_dev {
                                                 * fifo_size==0 implies no fifo
                                                 * if set, should be trsh+1
                                                 */
-       unsigned                rev1:1;
+       u8                      rev;
        unsigned                b_hw:1;         /* bad h/w fixes */
        unsigned                idle:1;
        u16                     iestate;        /* Saved interrupt register */
@@ -165,28 +200,17 @@ static int __init omap_i2c_get_clocks(struct omap_i2c_dev *dev)
                        return -ENODEV;
                }
        }
-       /* For I2C operations on 2430 we need 96Mhz clock */
-       if (cpu_is_omap2430()) {
-               dev->fclk = clk_get(dev->dev, "i2chs_fck");
-               if (IS_ERR(dev->fclk)) {
-                       if (dev->iclk != NULL) {
-                               clk_put(dev->iclk);
-                               dev->iclk = NULL;
-                       }
-                       dev->fclk = NULL;
-                       return -ENODEV;
-               }
-       } else {
-               dev->fclk = clk_get(dev->dev, "i2c_fck");
-               if (IS_ERR(dev->fclk)) {
-                       if (dev->iclk != NULL) {
-                               clk_put(dev->iclk);
-                               dev->iclk = NULL;
-                       }
-                       dev->fclk = NULL;
-                       return -ENODEV;
+
+       dev->fclk = clk_get(dev->dev, "i2c_fck");
+       if (IS_ERR(dev->fclk)) {
+               if (dev->iclk != NULL) {
+                       clk_put(dev->iclk);
+                       dev->iclk = NULL;
                }
+               dev->fclk = NULL;
+               return -ENODEV;
        }
+
        return 0;
 }
 
@@ -220,16 +244,14 @@ 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)
+       if (dev->rev < OMAP_I2C_REV_2) {
                iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
-       else
+       } else {
                omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
-       /*
-        * The wmb() is to ensure that the I2C interrupt mask write
-        * reaches the I2C controller before the dev->idle store
-        * occurs.
-        */
-       wmb();
+
+               /* Flush posted write before the dev->idle store occurs */
+               omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+       }
        dev->idle = 1;
        clk_disable(dev->fclk);
        if (dev->iclk != NULL)
@@ -244,14 +266,14 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
        unsigned long timeout;
        unsigned long internal_clk = 0;
 
-       if (!dev->rev1) {
-               omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, OMAP_I2C_SYSC_SRST);
+       if (dev->rev >= OMAP_I2C_REV_2) {
+               omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
                /* For some reason we need to set the EN bit before the
                 * reset done bit gets set. */
                timeout = jiffies + OMAP_I2C_TIMEOUT;
                omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
                while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
-                        OMAP_I2C_SYSS_RDONE)) {
+                        SYSS_RESETDONE_MASK)) {
                        if (time_after(jiffies, timeout)) {
                                dev_warn(dev->dev, "timeout waiting "
                                                "for controller reset\n");
@@ -259,6 +281,33 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
                        }
                        msleep(1);
                }
+
+               /* SYSC register is cleared by the reset; rewrite it */
+               if (dev->rev == OMAP_I2C_REV_ON_2430) {
+
+                       omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
+                                          SYSC_AUTOIDLE_MASK);
+
+               } else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
+                       u32 v;
+
+                       v = SYSC_AUTOIDLE_MASK;
+                       v |= SYSC_ENAWAKEUP_MASK;
+                       v |= (SYSC_IDLEMODE_SMART <<
+                             __ffs(SYSC_SIDLEMODE_MASK));
+                       v |= (SYSC_CLOCKACTIVITY_FCLK <<
+                             __ffs(SYSC_CLOCKACTIVITY_MASK));
+
+                       omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, v);
+                       /*
+                        * Enabling all wakup sources to stop I2C freezing on
+                        * WFI instruction.
+                        * REVISIT: Some wkup sources might not be needed.
+                        */
+                       omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
+                                                       OMAP_I2C_WE_ALL);
+
+               }
        }
        omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 
@@ -415,7 +464,7 @@ 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
+        * Don't write stt and stp together on some hardware.
         */
        if (dev->b_hw && stop) {
                unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
@@ -436,6 +485,11 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
                w &= ~OMAP_I2C_CON_STT;
                omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
        }
+
+       /*
+        * REVISIT: We should abort the transfer on signals, but the bus goes
+        * into arbitration and we're currently unable to recover from it.
+        */
        r = wait_for_completion_timeout(&dev->cmd_complete,
                                        OMAP_I2C_TIMEOUT);
        dev->buf_len = 0;
@@ -578,7 +632,7 @@ omap_i2c_rev1_isr(int this_irq, void *dev_id)
        return IRQ_HANDLED;
 }
 #else
-#define omap_i2c_rev1_isr              0
+#define omap_i2c_rev1_isr              NULL
 #endif
 
 static irqreturn_t
@@ -621,8 +675,9 @@ omap_i2c_isr(int this_irq, void *dev_id)
                                if (stat & OMAP_I2C_STAT_RRDY)
                                        num_bytes = dev->fifo_size;
                                else
-                                       num_bytes = omap_i2c_read_reg(dev,
-                                                       OMAP_I2C_BUFSTAT_REG);
+                                       num_bytes = (omap_i2c_read_reg(dev,
+                                                       OMAP_I2C_BUFSTAT_REG)
+                                                       >> 8) & 0x3F;
                        }
                        while (num_bytes) {
                                num_bytes--;
@@ -660,8 +715,9 @@ omap_i2c_isr(int this_irq, void *dev_id)
                                if (stat & OMAP_I2C_STAT_XRDY)
                                        num_bytes = dev->fifo_size;
                                else
-                                       num_bytes = omap_i2c_read_reg(dev,
-                                                       OMAP_I2C_BUFSTAT_REG);
+                                       num_bytes = (omap_i2c_read_reg(dev,
+                                                       OMAP_I2C_BUFSTAT_REG))
+                                                       & 0x3F;
                        }
                        while (num_bytes) {
                                num_bytes--;
@@ -718,8 +774,9 @@ omap_i2c_probe(struct platform_device *pdev)
        struct omap_i2c_dev     *dev;
        struct i2c_adapter      *adap;
        struct resource         *mem, *irq, *ioarea;
+       void *isr;
        int r;
-       u32 *speed = NULL;
+       u32 speed = 0;
 
        /* NOTE: driver uses the static register mapping */
        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -747,11 +804,11 @@ omap_i2c_probe(struct platform_device *pdev)
        }
 
        if (pdev->dev.platform_data != NULL)
-               speed = (u32 *) pdev->dev.platform_data;
+               speed = *(u32 *)pdev->dev.platform_data;
        else
-               *speed = 100; /* Defualt speed */
+               speed = 100;    /* Defualt speed */
 
-       dev->speed = *speed;
+       dev->speed = speed;
        dev->idle = 1;
        dev->dev = &pdev->dev;
        dev->irq = irq->start;
@@ -763,14 +820,12 @@ omap_i2c_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, dev);
 
-       r = omap_i2c_get_clocks(dev);
-       if (r != 0)
+       if ((r = omap_i2c_get_clocks(dev)) != 0)
                goto err_iounmap;
 
        omap_i2c_unidle(dev);
 
-       if (cpu_is_omap15xx())
-               dev->rev1 = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) < 0x20;
+       dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
 
        if (cpu_is_omap2430() || cpu_is_omap34xx()) {
                u16 s;
@@ -791,16 +846,16 @@ omap_i2c_probe(struct platform_device *pdev)
        /* reset ASAP, clearing any IRQs */
        omap_i2c_init(dev);
 
-       r = request_irq(dev->irq, dev->rev1 ? omap_i2c_rev1_isr : omap_i2c_isr,
-                       0, pdev->name, dev);
+       isr = (dev->rev < OMAP_I2C_REV_2) ? omap_i2c_rev1_isr : omap_i2c_isr;
+       r = request_irq(dev->irq, isr, 0, pdev->name, dev);
 
        if (r) {
                dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
                goto err_unuse_clocks;
        }
-       r = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
+
        dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n",
-                pdev->id, r >> 4, r & 0xf, dev->speed);
+                pdev->id, dev->rev >> 4, dev->rev & 0xf, dev->speed);
 
        omap_i2c_idle(dev);
 
@@ -868,14 +923,14 @@ static struct platform_driver omap_i2c_driver = {
 };
 
 /* I2C may be needed to bring up other drivers */
-static int __devinit
+static int __init
 omap_i2c_init_driver(void)
 {
        return platform_driver_register(&omap_i2c_driver);
 }
 subsys_initcall(omap_i2c_init_driver);
 
-static void __devexit omap_i2c_exit_driver(void)
+static void __exit omap_i2c_exit_driver(void)
 {
        platform_driver_unregister(&omap_i2c_driver);
 }