Re: [RFC PATCH 1/4] mmc: core: add cap-enhanced-strobe support

From: Shawn Lin
Date: Thu Mar 03 2016 - 20:39:58 EST


Hi Jaehoon,

On 2016/3/3 20:08, Jaehoon Chung wrote:
Hi Shawn,

On 03/03/2016 11:36 AM, Shawn Lin wrote:
This patch introduce cap-enhanced-strobe for platforms which
want to enable enhanced strobe function from DT if the mmc host
controller claims to support enhanced strobe.

I don't know why need to add the capability and property.


From my point, HS400-ES is a optional feature, so we should leave it
for people to decide whether to use it. Just as my controller supports hs400, but I can't force all the people using my platform to use hs400?
That's why we add mmc-hs400-* in DT.

But maybe I can change the name to mmc-hs400es-* ?


[...]

#define MMC_CAP_DRIVER_TYPE_A (1 << 23) /* Host supports Driver Type A */
#define MMC_CAP_DRIVER_TYPE_C (1 << 24) /* Host supports Driver Type C */
#define MMC_CAP_DRIVER_TYPE_D (1 << 25) /* Host supports Driver Type D */
+#define MMC_CAP_ENHANCED_STROBE (1 << 20) /* Host supports enhanced strobe */

Need to fix ordering.

yeah~~ good catch!


#define MMC_CAP_CMD23 (1 << 30) /* CMD23 supported. */
#define MMC_CAP_HW_RESET (1 << 31) /* Hardware reset */

@@ -469,6 +470,11 @@ static inline int mmc_host_uhs(struct mmc_host *host)
MMC_CAP_UHS_DDR50);
}

+static inline int mmc_host_enhanced_strobe(struct mmc_host *host)
+{
+ return host->caps & MMC_CAP_ENHANCED_STROBE;
+}
+
static inline int mmc_host_packed_wr(struct mmc_host *host)
{
return host->caps2 & MMC_CAP2_PACKED_WR;


--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html



--
Best Regards
Shawn Lin