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i2c-designware: Use local version of readl & writel
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Use local versions of readl & writel, so per-access manipulations may be performed

Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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Jean-Hugues Deschenes authored and Ben Dooks committed Oct 29, 2011
1 parent 1fdb24e commit 7f27960
Showing 1 changed file with 49 additions and 39 deletions.
88 changes: 49 additions & 39 deletions drivers/i2c/busses/i2c-designware.c
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Original file line number Diff line number Diff line change
Expand Up @@ -220,6 +220,16 @@ struct dw_i2c_dev {
unsigned int rx_fifo_depth;
};

static u32 dw_readl(struct dw_i2c_dev *dev, int offset)
{
return readl(dev->base + offset);
}

static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
{
writel(b, dev->base + offset);
}

static u32
i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset)
{
Expand Down Expand Up @@ -289,7 +299,7 @@ static void i2c_dw_init(struct dw_i2c_dev *dev)
u32 ic_con, hcnt, lcnt;

/* Disable the adapter */
writel(0, dev->base + DW_IC_ENABLE);
dw_writel(dev, 0, DW_IC_ENABLE);

/* set standard and fast speed deviders for high/low periods */

Expand All @@ -303,8 +313,8 @@ static void i2c_dw_init(struct dw_i2c_dev *dev)
47, /* tLOW = 4.7 us */
3, /* tf = 0.3 us */
0); /* No offset */
writel(hcnt, dev->base + DW_IC_SS_SCL_HCNT);
writel(lcnt, dev->base + DW_IC_SS_SCL_LCNT);
dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT);
dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT);
dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);

/* Fast-mode */
Expand All @@ -317,18 +327,18 @@ static void i2c_dw_init(struct dw_i2c_dev *dev)
13, /* tLOW = 1.3 us */
3, /* tf = 0.3 us */
0); /* No offset */
writel(hcnt, dev->base + DW_IC_FS_SCL_HCNT);
writel(lcnt, dev->base + DW_IC_FS_SCL_LCNT);
dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT);
dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);

/* Configure Tx/Rx FIFO threshold levels */
writel(dev->tx_fifo_depth - 1, dev->base + DW_IC_TX_TL);
writel(0, dev->base + DW_IC_RX_TL);
dw_writel(dev, dev->tx_fifo_depth - 1, DW_IC_TX_TL);
dw_writel(dev, 0, DW_IC_RX_TL);

/* configure the i2c master */
ic_con = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
writel(ic_con, dev->base + DW_IC_CON);
dw_writel(dev, ic_con, DW_IC_CON);
}

/*
Expand All @@ -338,7 +348,7 @@ static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
{
int timeout = TIMEOUT;

while (readl(dev->base + DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) {
while (dw_readl(dev, DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) {
if (timeout <= 0) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
return -ETIMEDOUT;
Expand All @@ -356,24 +366,24 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
u32 ic_con;

/* Disable the adapter */
writel(0, dev->base + DW_IC_ENABLE);
dw_writel(dev, 0, DW_IC_ENABLE);

/* set the slave (target) address */
writel(msgs[dev->msg_write_idx].addr, dev->base + DW_IC_TAR);
dw_writel(dev, msgs[dev->msg_write_idx].addr, DW_IC_TAR);

/* if the slave address is ten bit address, enable 10BITADDR */
ic_con = readl(dev->base + DW_IC_CON);
ic_con = dw_readl(dev, DW_IC_CON);
if (msgs[dev->msg_write_idx].flags & I2C_M_TEN)
ic_con |= DW_IC_CON_10BITADDR_MASTER;
else
ic_con &= ~DW_IC_CON_10BITADDR_MASTER;
writel(ic_con, dev->base + DW_IC_CON);
dw_writel(dev, ic_con, DW_IC_CON);

/* Enable the adapter */
writel(1, dev->base + DW_IC_ENABLE);
dw_writel(dev, 1, DW_IC_ENABLE);

/* Enable interrupts */
writel(DW_IC_INTR_DEFAULT_MASK, dev->base + DW_IC_INTR_MASK);
dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK);
}

/*
Expand Down Expand Up @@ -420,15 +430,15 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
buf_len = msgs[dev->msg_write_idx].len;
}

tx_limit = dev->tx_fifo_depth - readl(dev->base + DW_IC_TXFLR);
rx_limit = dev->rx_fifo_depth - readl(dev->base + DW_IC_RXFLR);
tx_limit = dev->tx_fifo_depth - dw_readl(dev, DW_IC_TXFLR);
rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR);

while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
writel(0x100, dev->base + DW_IC_DATA_CMD);
dw_writel(dev, 0x100, DW_IC_DATA_CMD);
rx_limit--;
} else
writel(*buf++, dev->base + DW_IC_DATA_CMD);
dw_writel(dev, *buf++, DW_IC_DATA_CMD);
tx_limit--; buf_len--;
}

Expand All @@ -453,7 +463,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
if (dev->msg_err)
intr_mask = 0;

writel(intr_mask, dev->base + DW_IC_INTR_MASK);
dw_writel(dev, intr_mask, DW_IC_INTR_MASK);
}

static void
Expand All @@ -477,10 +487,10 @@ i2c_dw_read(struct dw_i2c_dev *dev)
buf = dev->rx_buf;
}

rx_valid = readl(dev->base + DW_IC_RXFLR);
rx_valid = dw_readl(dev, DW_IC_RXFLR);

for (; len > 0 && rx_valid > 0; len--, rx_valid--)
*buf++ = readl(dev->base + DW_IC_DATA_CMD);
*buf++ = dw_readl(dev, DW_IC_DATA_CMD);

if (len > 0) {
dev->status |= STATUS_READ_IN_PROGRESS;
Expand Down Expand Up @@ -563,7 +573,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
/* no error */
if (likely(!dev->cmd_err)) {
/* Disable the adapter */
writel(0, dev->base + DW_IC_ENABLE);
dw_writel(dev, 0, DW_IC_ENABLE);
ret = num;
goto done;
}
Expand Down Expand Up @@ -607,7 +617,7 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
*
* The raw version might be useful for debugging purposes.
*/
stat = readl(dev->base + DW_IC_INTR_STAT);
stat = dw_readl(dev, DW_IC_INTR_STAT);

/*
* Do not use the IC_CLR_INTR register to clear interrupts, or
Expand All @@ -617,31 +627,31 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
* Instead, use the separately-prepared IC_CLR_* registers.
*/
if (stat & DW_IC_INTR_RX_UNDER)
readl(dev->base + DW_IC_CLR_RX_UNDER);
dw_readl(dev, DW_IC_CLR_RX_UNDER);
if (stat & DW_IC_INTR_RX_OVER)
readl(dev->base + DW_IC_CLR_RX_OVER);
dw_readl(dev, DW_IC_CLR_RX_OVER);
if (stat & DW_IC_INTR_TX_OVER)
readl(dev->base + DW_IC_CLR_TX_OVER);
dw_readl(dev, DW_IC_CLR_TX_OVER);
if (stat & DW_IC_INTR_RD_REQ)
readl(dev->base + DW_IC_CLR_RD_REQ);
dw_readl(dev, DW_IC_CLR_RD_REQ);
if (stat & DW_IC_INTR_TX_ABRT) {
/*
* The IC_TX_ABRT_SOURCE register is cleared whenever
* the IC_CLR_TX_ABRT is read. Preserve it beforehand.
*/
dev->abort_source = readl(dev->base + DW_IC_TX_ABRT_SOURCE);
readl(dev->base + DW_IC_CLR_TX_ABRT);
dev->abort_source = dw_readl(dev, DW_IC_TX_ABRT_SOURCE);
dw_readl(dev, DW_IC_CLR_TX_ABRT);
}
if (stat & DW_IC_INTR_RX_DONE)
readl(dev->base + DW_IC_CLR_RX_DONE);
dw_readl(dev, DW_IC_CLR_RX_DONE);
if (stat & DW_IC_INTR_ACTIVITY)
readl(dev->base + DW_IC_CLR_ACTIVITY);
dw_readl(dev, DW_IC_CLR_ACTIVITY);
if (stat & DW_IC_INTR_STOP_DET)
readl(dev->base + DW_IC_CLR_STOP_DET);
dw_readl(dev, DW_IC_CLR_STOP_DET);
if (stat & DW_IC_INTR_START_DET)
readl(dev->base + DW_IC_CLR_START_DET);
dw_readl(dev, DW_IC_CLR_START_DET);
if (stat & DW_IC_INTR_GEN_CALL)
readl(dev->base + DW_IC_CLR_GEN_CALL);
dw_readl(dev, DW_IC_CLR_GEN_CALL);

return stat;
}
Expand All @@ -666,7 +676,7 @@ static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
* Anytime TX_ABRT is set, the contents of the tx/rx
* buffers are flushed. Make sure to skip them.
*/
writel(0, dev->base + DW_IC_INTR_MASK);
dw_writel(dev, 0, DW_IC_INTR_MASK);
goto tx_aborted;
}

Expand Down Expand Up @@ -747,14 +757,14 @@ static int __devinit dw_i2c_probe(struct platform_device *pdev)
goto err_unuse_clocks;
}
{
u32 param1 = readl(dev->base + DW_IC_COMP_PARAM_1);
u32 param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);

dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
}
i2c_dw_init(dev);

writel(0, dev->base + DW_IC_INTR_MASK); /* disable IRQ */
dw_writel(dev, 0, DW_IC_INTR_MASK); /* disable IRQ */
r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
Expand Down Expand Up @@ -810,7 +820,7 @@ static int __devexit dw_i2c_remove(struct platform_device *pdev)
clk_put(dev->clk);
dev->clk = NULL;

writel(0, dev->base + DW_IC_ENABLE);
dw_writel(dev, 0, DW_IC_ENABLE);
free_irq(dev->irq, dev);
kfree(dev);

Expand Down

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