[PATCH 5/8] i2c: omap: introduce and use OMAP_I2C_IP_VERSION_3

[Felipe Balbi]

Hi,

On Mon, Oct 22, 2012 at 02:27:20PM +0200, Benoit Cousson wrote:
> Hi Felipe,
> 
> On 10/22/2012 11:46 AM, Felipe Balbi wrote:
> > on OMAP4+ we want to read IRQSTATUS_RAW register,
> > instead of IRQSTATUS. The reason being that IRQSTATUS
> > will only contain the bits which were enabled on
> > IRQENABLE_SET and that will break when we need to
> > poll for a certain bit which wasn't enabled as an
> > IRQ source.
> > 
> > One such case is after we finish converting to
> > deferred stop bit, we will have to poll for ARDY
> > bit before returning control for the client driver
> > in order to prevent us from trying to start a
> > transfer on a bus which is already busy.
> > 
> > Note, however, that omap-i2c.c needs a big rework
> > on register definition and register access. Such
> > work will be done in a separate series of patches.
> 
> Do you need OMAP_I2C_IP_VERSION_3 for OMAP4?
> 
> OMAP_I2C_IP_VERSION_2 was already introduced to detect OMAP3630 vs
> omap4430 because they were sharing the same IP version..
> 
> /* I2C controller revisions present on specific hardware */
> #define OMAP_I2C_REV_ON_2430            0x36
> #define OMAP_I2C_REV_ON_3430_3530       0x3C
> #define OMAP_I2C_REV_ON_3630_4430       0x40
> 
> So in theory you should not need an extra version.

are you sure that's how they're used ? Looking at the code where we
choose reg_map_ip_v1 and reg_map_ip_v2:

1120         if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
1121                 dev->regs = (u8 *)reg_map_ip_v2;
1122         else
1123                 dev->regs = (u8 *)reg_map_ip_v1;

And looking at reg_map_ip_v1:

 218 static const u8 reg_map_ip_v1[] = {
 219         [OMAP_I2C_REV_REG] = 0x00,
 220         [OMAP_I2C_IE_REG] = 0x01,
 221         [OMAP_I2C_STAT_REG] = 0x02,
 222         [OMAP_I2C_IV_REG] = 0x03,
 223         [OMAP_I2C_WE_REG] = 0x03,
 224         [OMAP_I2C_SYSS_REG] = 0x04,
 225         [OMAP_I2C_BUF_REG] = 0x05,
 226         [OMAP_I2C_CNT_REG] = 0x06,
 227         [OMAP_I2C_DATA_REG] = 0x07,
 228         [OMAP_I2C_SYSC_REG] = 0x08,
 229         [OMAP_I2C_CON_REG] = 0x09,
 230         [OMAP_I2C_OA_REG] = 0x0a,
 231         [OMAP_I2C_SA_REG] = 0x0b,
 232         [OMAP_I2C_PSC_REG] = 0x0c,
 233         [OMAP_I2C_SCLL_REG] = 0x0d,
 234         [OMAP_I2C_SCLH_REG] = 0x0e,
 235         [OMAP_I2C_SYSTEST_REG] = 0x0f,
 236         [OMAP_I2C_BUFSTAT_REG] = 0x10,
 237 };

that's really not the register map on OMAP3. That only looks valid for
OMAP1.

-ECONFUSED

-- 
balbi
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20121022/d5deb0e8/attachment.sig>