[PATCH] mmc: core: sd: check card write-protect lock while resuming

[Barry Song]

> -----Original Message-----
> From: Ulf Hansson [mailto:ulf.hansson at linaro.org]
> Sent: Monday, August 18, 2014 7:58 PM
> To: Barry Song
> Cc: Chris Ball; linux-mmc; linux-arm-kernel at lists.infradead.org; DL-SHA-
> WorkGroupLinux; Minda Chen; Barry Song
> Subject: Re: [PATCH] mmc: core: sd: check card write-protect lock while
> resuming
> 
> On 18 August 2014 12:00, Barry Song <Barry.Song at csr.com> wrote:
> > From: Minda Chen <Minda.Chen at csr.com>
> >
> > After suspending, unplug the sdcard, and set sd WP lock, insert it
> > again, then resume the system. resume codes do not check the the
> > sdcard write-proctect lock. now check it.
> >
> > Signed-off-by: Minda Chen <Minda.Chen at csr.com>
> > Signed-off-by: Barry Song <Baohua.Song at csr.com>
> > ---
> >  drivers/mmc/core/sd.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> >
> > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index
> > 0c44510..890557a 100644
> > --- a/drivers/mmc/core/sd.c
> > +++ b/drivers/mmc/core/sd.c
> > @@ -910,6 +910,7 @@ static int mmc_sd_init_card(struct mmc_host
> *host, u32 ocr,
> >         int err;
> >         u32 cid[4];
> >         u32 rocr = 0;
> > +       bool oldro, ro;
> >
> >         BUG_ON(!host);
> >         WARN_ON(!host->claimed);
> > @@ -922,6 +923,12 @@ static int mmc_sd_init_card(struct mmc_host
> *host, u32 ocr,
> >                 if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0)
> >                         return -ENOENT;
> >
> > +               if (host->ops->get_ro) {
> > +                       ro = host->ops->get_ro(host) ? true : false;
> > +                       oldro = mmc_card_readonly(oldcard) ? true : false;
> > +                       if (oldro ^ ro)
> > +                               return -ENOENT;
> > +               }
> 
> Seems like this code belongs better in mmc_sd_setup_card(). Could you try
> moving it there.
[Barry Song] 
Well. How about:

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 0c44510..643bc82d8 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -815,6 +815,7 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
 	bool reinit)
 {
 	int err;
+	int oldro, ro = -1;
 
 	if (!reinit) {
 		/*
@@ -861,23 +862,28 @@ int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
 	/*
 	 * Check if read-only switch is active.
 	 */
-	if (!reinit) {
-		int ro = -1;
 
-		if (host->ops->get_ro) {
-			mmc_host_clk_hold(card->host);
-			ro = host->ops->get_ro(host);
-			mmc_host_clk_release(card->host);
-		}
+	if (host->ops->get_ro) {
+		mmc_host_clk_hold(card->host);
+		ro = host->ops->get_ro(host);
+		mmc_host_clk_release(card->host);
+	}
 
-		if (ro < 0) {
-			pr_warning("%s: host does not "
-				"support reading read-only "
-				"switch. assuming write-enable.\n",
-				mmc_hostname(host));
-		} else if (ro > 0) {
-			mmc_card_set_readonly(card);
-		}
+	if (ro < 0)
+		pr_warning("%s: host does not "
+			"support reading read-only "
+			"switch. assuming write-enable.\n",
+			mmc_hostname(host));
+
+	if (!reinit && (ro > 0))
+		mmc_card_set_readonly(card);
+	else if (reinit && (ro >= 0)) {
+		/* check if the write-protection lock is changed */
+		oldro = mmc_card_readonly(card) ? 1 : 0;
+		ro = (ro > 0) ? 1 : 0;
+
+		if (oldro ^ ro)
+			return -ENOENT;
 	}
 
 	return 0;
> 
> Kind regards
> Uffe
> 
> >                 card = oldcard;
> >         } else {
> >                 /*
-barry



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