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sdio: allow non-standard SDIO cards

PATCH In review [email protected] 2 participants 2 messages Aug 11, 2010 MMC, SD and SDIO

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PATCH 44/177 sdio: allow non-standard SDIO cards

From: Grazvydas Ignotas <[email protected]>

There are some chips (like TI WL12xx series) that can be interfaced over SDIO but don't support the SDIO specification, meaning that they are missing CIA (Common I/O Area) with all it's registers. Current Linux SDIO implementation relies on those registers to identify and configure the card, so non-standard cards can not function and cause lots of warnings from the core when it reads invalid data from non-existent registers.

After this patch, init_card() host callback can now set new quirk MMC_QUIRK_NONSTD_SDIO, which means that SDIO core should not try to access any standard SDIO registers and rely on init_card() to fill all SDIO structures instead. As those cards are usually embedded chips, all the required information can be obtained from machine board files by the host driver when it's called through init_card() callback.

Signed-off-by Grazvydas Ignotas <[email protected]>
Cc Adrian Hunter <[email protected]>
Cc Tony Lindgren <[email protected]>
Cc Bob Copeland <[email protected]>
Cc Kalle Valo <[email protected]>
Cc Madhusudhan Chikkature <[email protected]>
Cc Kishore Kadiyala <[email protected]>
Cc Russell King <[email protected]>
Cc <[email protected]>
Signed-off-by Andrew Morton <[email protected]>

---

 drivers/mmc/core/sdio.c  |   36 ++++++++++++++++++++++++++++++------
 include/linux/mmc/card.h |    2 ++
 2 files changed, 32 insertions(+), 6 deletions(-)
drivers/mmc/core/sdio.c renamed from drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards +30 -6
diff -puN drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards drivers/mmc/core/sdio.c
@@ -63,13 +63,19 @@ static int sdio_init_func(struct mmc_car
 
 	func->num = fn;
 
-	ret = sdio_read_fbr(func);
-	if (ret)
-		goto fail;
+	if (!(card->quirks & MMC_QUIRK_NONSTD_SDIO)) {
+		ret = sdio_read_fbr(func);
+		if (ret)
+			goto fail;
 
-	ret = sdio_read_func_cis(func);
-	if (ret)
-		goto fail;
+		ret = sdio_read_func_cis(func);
+		if (ret)
+			goto fail;
+	} else {
+		func->vendor = func->card->cis.vendor;
+		func->device = func->card->cis.device;
+		func->max_blksize = func->card->cis.blksize;
+	}
 
 	card->sdio_func[fn - 1] = func;
 

@@ -412,6 +418,23 @@ static int mmc_sdio_init_card(struct mmc
 			goto remove;
 	}
 
+	if (card->quirks & MMC_QUIRK_NONSTD_SDIO) {
+		/*
+		 * This is non-standard SDIO device, meaning it doesn't
+		 * have any CIA (Common I/O area) registers present.
+		 * It's host's responsibility to fill cccr and cis
+		 * structures in init_card().
+		 */
+		mmc_set_clock(host, card->cis.max_dtr);
+
+		if (card->cccr.high_speed) {
+			mmc_card_set_highspeed(card);
+			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
+		}
+
+		goto finish;
+	}
+
 	/*
 	 * Read the common registers.
 	 */

@@ -480,6 +503,7 @@ static int mmc_sdio_init_card(struct mmc
 	else if (err)
 		goto remove;
 
+finish:
 	if (!oldcard)
 		host->card = card;
 	return 0;
include/linux/mmc/card.h renamed from include/linux/mmc/card.h~sdio-allow-non-standard-sdio-cards +2 -0
diff -puN include/linux/mmc/card.h~sdio-allow-non-standard-sdio-cards include/linux/mmc/card.h
@@ -103,6 +103,8 @@ struct mmc_card {
 #define MMC_QUIRK_LENIENT_FN0	(1<<0)		/* allow SDIO FN0 writes outside of the VS CCCR range */
 #define MMC_QUIRK_BLKSZ_FOR_BYTE_MODE (1<<1)	/* use func->cur_blksize */
 						/* for byte mode */
+#define MMC_QUIRK_NONSTD_SDIO	(1<<2)		/* non-standard SDIO card attached */
+						/* (missing CIA registers) */
 
 	u32			raw_cid[4];	/* raw card CID */
 	u32			raw_csd[4];	/* raw card CSD */

_

#1 lore raw

2010/8/11 <[email protected]>:

Quoted 16 lines

From: Grazvydas Ignotas <[email protected]>

There are some chips (like TI WL12xx series) that can be interfaced over SDIO but don't support the SDIO specification, meaning that they are missing CIA (Common I/O Area) with all it's registers.  Current Linux SDIO implementation relies on those registers to identify and configure the card, so non-standard cards can not function and cause lots of warnings from the core when it reads invalid data from non-existent registers.

After this patch, init_card() host callback can now set new quirk MMC_QUIRK_NONSTD_SDIO, which means that SDIO core should not try to access any standard SDIO registers and rely on init_card() to fill all SDIO structures instead.  As those cards are usually embedded chips, all the required information can be obtained from machine board files by the host driver when it's called through init_card() callback.

[...]

Quoted 3 lines

diff -puN drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards drivers/mmc/core/sdio.c

drivers/mmc/core/sdio.c renamed from drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards +0 -0

[...]

Quoted 8 lines
drivers/mmc/core/sdio.c renamed from drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards +4 -0
@@ -412,6 +418,23 @@ static int mmc_sdio_init_card(struct mmc
                        goto remove;
        }
 
+       if (card->quirks & MMC_QUIRK_NONSTD_SDIO) {
+               /*
+                * This is non-standard SDIO device, meaning it doesn't
+                * have any CIA (Common I/O area) registers present.

drivers/mmc/core/sdio.c static int mmc_sdio_init_card(struct mmc · line 434

Quoted 10 lines
drivers/mmc/core/sdio.c renamed from drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards +9 -0
+                * It's host's responsibility to fill cccr and cis
+                * structures in init_card().
+                */
+               mmc_set_clock(host, card->cis.max_dtr);
+
 
+               if (card->cccr.high_speed) {
+                       mmc_card_set_highspeed(card);
+                       mmc_set_timing(card->host, MMC_TIMING_SD_HS);
+               }

Since this goes after patch 032/177 "mmc: split mmc_sd_init_card()", you can use:

    if (card->cccr.high_speed)
        mmc_sd_go_highspeed(card);
Quoted 7 lines
drivers/mmc/core/sdio.c renamed from drivers/mmc/core/sdio.c~sdio-allow-non-standard-sdio-cards +4 -0
+
+               goto finish;
+       }
+
        /*
         * Read the common registers.

        */

[...]

Best Regards,
Michał Mirosław