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i2c: imx: disable clock when it's possible to save power.

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Enable clock before START, disable it after STOP.

Signed-off-by: Richard Zhao <linuxzsc@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Richard Zhao 2009-10-17 17:46:24 +08:00 committed by Ben Dooks
parent a4094a76e6
commit db3a3d4ef7
1 changed files with 6 additions and 6 deletions
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12
drivers/i2c/busses/i2c-imx.c
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@ -121,6 +121,7 @@ struct imx_i2c_struct {
unsigned long i2csr;
unsigned int disable_delay;
int stopped;
unsigned int ifdr; /* IMX_I2C_IFDR */
};
/** Functions for IMX I2C adapter driver ***************************************
@ -192,6 +193,8 @@ static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
clk_enable(i2c_imx->clk);
writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
/* Enable I2C controller */
writeb(0, i2c_imx->base + IMX_I2C_I2SR);
writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
@ -238,6 +241,7 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
/* Disable I2C controller */
writeb(0, i2c_imx->base + IMX_I2C_I2CR);
clk_disable(i2c_imx->clk);
}
static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
@ -257,8 +261,8 @@ static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
else
for (i = 0; i2c_clk_div[i][0] < div; i++);
/* Write divider value to register */
writeb(i2c_clk_div[i][1], i2c_imx->base + IMX_I2C_IFDR);
/* Store divider value */
i2c_imx->ifdr = i2c_clk_div[i][1];
/*
* There dummy delay is calculated.
@ -528,7 +532,6 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "can't get I2C clock\n");
goto fail3;
}
clk_enable(i2c_imx->clk);
/* Request IRQ */
ret = request_irq(i2c_imx->irq, i2c_imx_isr, 0, pdev->name, i2c_imx);
@ -577,7 +580,6 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
fail5:
free_irq(i2c_imx->irq, i2c_imx);
fail4:
clk_disable(i2c_imx->clk);
clk_put(i2c_imx->clk);
fail3:
release_mem_region(i2c_imx->res->start, resource_size(res));
@ -614,8 +616,6 @@ static int __exit i2c_imx_remove(struct platform_device *pdev)
if (pdata && pdata->exit)
pdata->exit(&pdev->dev);
/* Disable I2C clock */
clk_disable(i2c_imx->clk);
clk_put(i2c_imx->clk);
release_mem_region(i2c_imx->res->start, resource_size(i2c_imx->res));