[PATCH] i2c: omap: re-factor omap_i2c_init function
Felipe Balbi
balbi at ti.com
Tue Oct 23 13:18:40 EDT 2012
Hi,
On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
> re-factor omap_i2c_init() so that we can re-use it for resume.
> While at it also remove the bufstate variable as we write it
> in omap_i2c_resize_fifo for every transfer.
>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti at ti.com>
> ---
> Applies on Felipe's series
> http://www.spinics.net/lists/linux-omap/msg79995.html
>
> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
> on omap3636 beagle both idle and suspend.
>
> Functional testing on omap4sdp.
>
> drivers/i2c/busses/i2c-omap.c | 68 +++++++++++++++++------------------------
> 1 files changed, 28 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 5e5cefb..338cee7 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
> u16 pscstate;
> u16 scllstate;
> u16 sclhstate;
> - u16 bufstate;
> u16 syscstate;
> u16 westate;
> u16 errata;
> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
> }
> }
>
> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
> +{
> +
> + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> + /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> + omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
> +
> + /* SCL low and high time values */
> + omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
> + omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
> + if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
> + omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
> + /* Take the I2C module out of reset: */
> + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> + omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> +
> +}
> static int omap_i2c_init(struct omap_i2c_dev *dev)
> {
> - u16 psc = 0, scll = 0, sclh = 0, buf = 0;
> + u16 psc = 0, scll = 0, sclh = 0;
> u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
> unsigned long fclk_rate = 12000000;
> unsigned long timeout;
> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> * REVISIT: Some wkup sources might not be needed.
> */
> dev->westate = OMAP_I2C_WE_ALL;
> - omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
> - dev->westate);
> }
> }
> - omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>
> if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
> /*
> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
> }
>
> - /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> - omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
> -
> - /* SCL low and high time values */
> - omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
> - omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
> -
> - /* Take the I2C module out of reset: */
> - omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -
> /* Enable interrupts */
> dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
> OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL) |
> ((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
> OMAP_I2C_IE_XDR) : 0);
> - omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> - if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> - dev->pscstate = psc;
> - dev->scllstate = scll;
> - dev->sclhstate = sclh;
> - dev->bufstate = buf;
> - }
> +
> + dev->pscstate = psc;
> + dev->scllstate = scll;
> + dev->sclhstate = sclh;
> +
> + __omap_i2c_init(dev);
> +
> return 0;
> }
>
> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
> if (IS_ERR_VALUE(r))
> goto err_free_mem;
>
> - dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
> + dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
trailing change. not part of $SUBJECT
> dev->errata = 0;
>
> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
> {
> struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>
> - if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> - omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> - omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> - omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> - omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> - omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> - omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> - omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> - omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> - }
> -
> - /*
> - * Don't write to this register if the IE state is 0 as it can
> - * cause deadlock.
> - */
> - if (_dev->iestate)
> - omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
this part is not on __omap_i2c_init() so you're potentially causing a
regression here.
> + if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
> + __omap_i2c_init(_dev);
how has this been tested ? Did you validate suspend to ram and runtime
pm ?
> return 0;
> }
> --
> 1.7.5.4
>
> --
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--
balbi
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