]> git.sur5r.net Git - u-boot/blobdiff - drivers/i2c/i2c-cdns.c
Remove unnecessary instances of DECLARE_GLOBAL_DATA_PTR
[u-boot] / drivers / i2c / i2c-cdns.c
index ef85a70ed3860413b1af12c3bbb88a438b81e9ac..a977a7fcbd3769ebd75ad2aa9efbc7f2b1054453 100644 (file)
@@ -9,16 +9,15 @@
  */
 
 #include <common.h>
+#include <dm.h>
 #include <linux/types.h>
 #include <linux/io.h>
 #include <linux/errno.h>
-#include <dm/device.h>
 #include <dm/root.h>
 #include <i2c.h>
 #include <fdtdec.h>
 #include <mapmem.h>
-
-DECLARE_GLOBAL_DATA_PTR;
+#include <wait_bit.h>
 
 /* i2c register set */
 struct cdns_i2c_regs {
@@ -67,6 +66,9 @@ struct cdns_i2c_regs {
 
 #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)
 
 #ifdef DEBUG
 static void cdns_i2c_debug_status(struct cdns_i2c_regs *cdns_i2c)
@@ -114,6 +116,13 @@ struct i2c_cdns_bus {
        int id;
        unsigned int input_freq;
        struct cdns_i2c_regs __iomem *regs;     /* register base */
+
+       int hold_flag;
+       u32 quirks;
+};
+
+struct cdns_i2c_platform_data {
+       u32 quirks;
 };
 
 /* Wait for an interrupt */
@@ -122,10 +131,10 @@ static u32 cdns_i2c_wait(struct cdns_i2c_regs *cdns_i2c, u32 mask)
        int timeout, int_status;
 
        for (timeout = 0; timeout < 100; timeout++) {
-               udelay(100);
                int_status = readl(&cdns_i2c->interrupt_status);
                if (int_status & mask)
                        break;
+               udelay(100);
        }
 
        /* Clear interrupt status flags */
@@ -215,43 +224,25 @@ static int cdns_i2c_set_bus_speed(struct udevice *dev, unsigned int speed)
        return 0;
 }
 
-/* Probe to see if a chip is present. */
-static int cdns_i2c_probe_chip(struct udevice *bus, uint chip_addr,
-                               uint chip_flags)
-{
-       struct i2c_cdns_bus *i2c_bus = dev_get_priv(bus);
-       struct cdns_i2c_regs *regs = i2c_bus->regs;
-
-       /* Attempt to read a byte */
-       setbits_le32(&regs->control, CDNS_I2C_CONTROL_CLR_FIFO |
-               CDNS_I2C_CONTROL_RW);
-       clrbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
-       writel(0xFF, &regs->interrupt_status);
-       writel(chip_addr, &regs->address);
-       writel(1, &regs->transfer_size);
-
-       return (cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP |
-               CDNS_I2C_INTERRUPT_NACK) &
-               CDNS_I2C_INTERRUPT_COMP) ? 0 : -ETIMEDOUT;
-}
-
 static int cdns_i2c_write_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
-                              u32 len, bool next_is_read)
+                              u32 len)
 {
        u8 *cur_data = data;
-
        struct cdns_i2c_regs *regs = i2c_bus->regs;
 
-       setbits_le32(&regs->control, CDNS_I2C_CONTROL_CLR_FIFO |
-               CDNS_I2C_CONTROL_HOLD);
-
-       /* if next is a read, we need to clear HOLD, doesn't work */
-       if (next_is_read)
-               clrbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
-
+       /* Set the controller in Master transmit mode and clear FIFO */
+       setbits_le32(&regs->control, CDNS_I2C_CONTROL_CLR_FIFO);
        clrbits_le32(&regs->control, CDNS_I2C_CONTROL_RW);
 
+       /* Check message size against FIFO depth, and set hold bus bit
+        * if it is greater than FIFO depth
+        */
+       if (len > CDNS_I2C_FIFO_DEPTH)
+               setbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
+
+       /* Clear the interrupts in status register */
        writel(0xFF, &regs->interrupt_status);
+
        writel(addr, &regs->address);
 
        while (len--) {
@@ -267,54 +258,107 @@ static int cdns_i2c_write_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
        }
 
        /* All done... release the bus */
-       clrbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
+       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))
                return -ETIMEDOUT;
        return 0;
 }
 
+static inline bool cdns_is_hold_quirk(int hold_quirk, int curr_recv_count)
+{
+       return hold_quirk && (curr_recv_count == CDNS_I2C_FIFO_DEPTH + 1);
+}
+
 static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data,
-                             u32 len)
+                             u32 recv_count)
 {
-       u32 status;
-       u32 i = 0;
        u8 *cur_data = data;
-
-       /* TODO: Fix this */
        struct cdns_i2c_regs *regs = i2c_bus->regs;
+       int curr_recv_count;
+       int updatetx, hold_quirk;
 
        /* Check the hardware can handle the requested bytes */
-       if ((len < 0) || (len > CDNS_I2C_TRANSFER_SIZE_MAX))
+       if ((recv_count < 0))
                return -EINVAL;
 
+       curr_recv_count = recv_count;
+
+       /* Check for the message size against the FIFO depth */
+       if (recv_count > CDNS_I2C_FIFO_DEPTH)
+               setbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
+
        setbits_le32(&regs->control, CDNS_I2C_CONTROL_CLR_FIFO |
                CDNS_I2C_CONTROL_RW);
 
+       if (recv_count > CDNS_I2C_TRANSFER_SIZE) {
+               curr_recv_count = CDNS_I2C_TRANSFER_SIZE;
+               writel(curr_recv_count, &regs->transfer_size);
+       } else {
+               writel(recv_count, &regs->transfer_size);
+       }
+
        /* Start reading data */
        writel(addr, &regs->address);
-       writel(len, &regs->transfer_size);
-
-       /* Wait for data */
-       do {
-               status = cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP |
-                       CDNS_I2C_INTERRUPT_DATA);
-               if (!status) {
-                       /* Release the bus */
-                       clrbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
-                       return -ETIMEDOUT;
+
+       updatetx = recv_count > curr_recv_count;
+
+       hold_quirk = (i2c_bus->quirks & CDNS_I2C_BROKEN_HOLD_BIT) && updatetx;
+
+       while (recv_count) {
+               while (readl(&regs->status) & CDNS_I2C_STATUS_RXDV) {
+                       if (recv_count < CDNS_I2C_FIFO_DEPTH &&
+                           !i2c_bus->hold_flag) {
+                               clrbits_le32(&regs->control,
+                                            CDNS_I2C_CONTROL_HOLD);
+                       }
+                       *(cur_data)++ = readl(&regs->data);
+                       recv_count--;
+                       curr_recv_count--;
+
+                       if (cdns_is_hold_quirk(hold_quirk, curr_recv_count))
+                               break;
                }
-               debug("Read %d bytes\n",
-                     len - readl(&regs->transfer_size));
-               for (; i < len - readl(&regs->transfer_size); i++)
-                       *(cur_data++) = readl(&regs->data);
-       } while (readl(&regs->transfer_size) != 0);
-       /* All done... release the bus */
-       clrbits_le32(&regs->control, CDNS_I2C_CONTROL_HOLD);
 
-#ifdef DEBUG
-       cdns_i2c_debug_status(regs);
-#endif
+               if (cdns_is_hold_quirk(hold_quirk, curr_recv_count)) {
+                       /* wait while fifo is full */
+                       while (readl(&regs->transfer_size) !=
+                                    (curr_recv_count - CDNS_I2C_FIFO_DEPTH))
+                               ;
+                       /*
+                        * Check number of bytes to be received against maximum
+                        * transfer size and update register accordingly.
+                        */
+                       if ((recv_count - CDNS_I2C_FIFO_DEPTH) >
+                           CDNS_I2C_TRANSFER_SIZE) {
+                               writel(CDNS_I2C_TRANSFER_SIZE,
+                                      &regs->transfer_size);
+                               curr_recv_count = CDNS_I2C_TRANSFER_SIZE +
+                                       CDNS_I2C_FIFO_DEPTH;
+                       } else {
+                               writel(recv_count - CDNS_I2C_FIFO_DEPTH,
+                                      &regs->transfer_size);
+                               curr_recv_count = recv_count;
+                       }
+               } else if (recv_count && !hold_quirk && !curr_recv_count) {
+                       writel(addr, &regs->address);
+                       if (recv_count > CDNS_I2C_TRANSFER_SIZE) {
+                               writel(CDNS_I2C_TRANSFER_SIZE,
+                                      &regs->transfer_size);
+                               curr_recv_count = CDNS_I2C_TRANSFER_SIZE;
+                       } else {
+                               writel(recv_count, &regs->transfer_size);
+                               curr_recv_count = recv_count;
+                       }
+               }
+       }
+
+       /* Wait for the address and data to be sent */
+       if (!cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP))
+               return -ETIMEDOUT;
+
        return 0;
 }
 
@@ -322,19 +366,41 @@ 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;
+       int ret, count;
+       bool hold_quirk;
+
+       hold_quirk = !!(i2c_bus->quirks & CDNS_I2C_BROKEN_HOLD_BIT);
+
+       if (nmsgs > 1) {
+               /*
+                * This controller does not give completion interrupt after a
+                * master receive message if HOLD bit is set (repeated start),
+                * resulting in SW timeout. Hence, if a receive message is
+                * followed by any other message, an error is returned
+                * indicating that this sequence is not supported.
+                */
+               for (count = 0; (count < nmsgs - 1) && hold_quirk; count++) {
+                       if (msg[count].flags & I2C_M_RD) {
+                               printf("Can't do repeated start after a receive message\n");
+                               return -EOPNOTSUPP;
+                       }
+               }
+
+               i2c_bus->hold_flag = 1;
+               setbits_le32(&i2c_bus->regs->control, CDNS_I2C_CONTROL_HOLD);
+       } else {
+               i2c_bus->hold_flag = 0;
+       }
 
        debug("i2c_xfer: %d messages\n", nmsgs);
        for (; nmsgs > 0; nmsgs--, msg++) {
-               bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
-
                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,
                                                 msg->len);
                } else {
                        ret = cdns_i2c_write_data(i2c_bus, msg->addr, msg->buf,
-                                                 msg->len, next_is_read);
+                                                 msg->len);
                }
                if (ret) {
                        debug("i2c_write: error sending\n");
@@ -348,11 +414,16 @@ static int cdns_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
 static int cdns_i2c_ofdata_to_platdata(struct udevice *dev)
 {
        struct i2c_cdns_bus *i2c_bus = dev_get_priv(dev);
+       struct cdns_i2c_platform_data *pdata =
+               (struct cdns_i2c_platform_data *)dev_get_driver_data(dev);
 
-       i2c_bus->regs = (struct cdns_i2c_regs *)dev_get_addr(dev);
+       i2c_bus->regs = (struct cdns_i2c_regs *)devfdt_get_addr(dev);
        if (!i2c_bus->regs)
                return -ENOMEM;
 
+       if (pdata)
+               i2c_bus->quirks = pdata->quirks;
+
        i2c_bus->input_freq = 100000000; /* TODO hardcode input freq for now */
 
        return 0;
@@ -360,12 +431,15 @@ static int cdns_i2c_ofdata_to_platdata(struct udevice *dev)
 
 static const struct dm_i2c_ops cdns_i2c_ops = {
        .xfer = cdns_i2c_xfer,
-       .probe_chip = cdns_i2c_probe_chip,
        .set_bus_speed = cdns_i2c_set_bus_speed,
 };
 
+static const struct cdns_i2c_platform_data r1p10_i2c_def = {
+       .quirks = CDNS_I2C_BROKEN_HOLD_BIT,
+};
+
 static const struct udevice_id cdns_i2c_of_match[] = {
-       { .compatible = "cdns,i2c-r1p10" },
+       { .compatible = "cdns,i2c-r1p10", .data = (ulong)&r1p10_i2c_def },
        { .compatible = "cdns,i2c-r1p14" },
        { /* end of table */ }
 };