mmc: Change board_mmc_getcd() function prototype.

The new API no longer uses the extra cd parameter that was used to store
the card presence state. Instead, this information is returned via the
function's return value. board_mmc_getcd() returns -1 to indicate that
no card-detection mechanism is implemented; 0 indicates that no card is
present and 1 is returned if it was detected that a card is present.

The rationale for this change can be found in the following email
thread:

	http://lists.denx.de/pipermail/u-boot/2011-November/110180.html

In summary, the old API was not consistent with the rest of the MMC API
which always passes a struct mmc as the first parameter. Furthermore the
cd parameter was used to mean "card absence" in some implementations and
"card presence" in others.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Tested-by: Jason Liu <jason.hui@linaro.org>

board/efikamx/efikamx.c

@@ -314,17 +314,18 @@ static inline uint32_t efika_mmc_cd(void)
 		return MX51_PIN_EIM_CS2;
 }
 
-int board_mmc_getcd(u8 *absent, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
 	struct fsl_esdhc_cfg *cfg = (struct fsl_esdhc_cfg *)mmc->priv;
 	uint32_t cd = efika_mmc_cd();
+	int ret;
 
 	if (cfg->esdhc_base == MMC_SDHC1_BASE_ADDR)
-		*absent = gpio_get_value(IOMUX_TO_GPIO(cd));
+		ret = !gpio_get_value(IOMUX_TO_GPIO(cd));
 	else
-		*absent = gpio_get_value(IOMUX_TO_GPIO(MX51_PIN_GPIO1_8));
+		ret = !gpio_get_value(IOMUX_TO_GPIO(MX51_PIN_GPIO1_8));
 
-	return 0;
+	return ret;
 }
 
 int board_mmc_init(bd_t *bis)

board/emk/top9000/top9000.c

@@ -108,17 +108,9 @@ int board_mmc_init(bd_t *bd)
 }
 
 /* this is a weak define that we are overriding */
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
-	/*
-	 * the only currently existing use of this function
-	 * (fsl_esdhc.c) suggests this function must return
-	 * *cs = TRUE if a card is NOT detected -> in most
-	 * cases the value of the pin when the detect switch
-	 * closes to GND
-	 */
-	*cd = at91_get_gpio_value(CONFIG_SYS_MMC_CD_PIN) ? 1 : 0;
-	return 0;
+	return !at91_get_gpio_value(CONFIG_SYS_MMC_CD_PIN);
 }
 
 #endif

board/freescale/mx51evk/mx51evk.c

@@ -321,19 +321,20 @@ static void power_init(void)
 }
 
 #ifdef CONFIG_FSL_ESDHC
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
 	struct fsl_esdhc_cfg *cfg = (struct fsl_esdhc_cfg *)mmc->priv;
+	int ret;
 
 	mxc_request_iomux(MX51_PIN_GPIO1_0, IOMUX_CONFIG_ALT1);
 	mxc_request_iomux(MX51_PIN_GPIO1_6, IOMUX_CONFIG_ALT0);
 
 	if (cfg->esdhc_base == MMC_SDHC1_BASE_ADDR)
-		*cd = gpio_get_value(0);
+		ret = !gpio_get_value(0);
 	else
-		*cd = gpio_get_value(6);
+		ret = !gpio_get_value(6);
 
-	return 0;
+	return ret;
 }
 
 int board_mmc_init(bd_t *bis)

board/freescale/mx53ard/mx53ard.c

@@ -83,19 +83,20 @@ struct fsl_esdhc_cfg esdhc_cfg[2] = {
 	{MMC_SDHC2_BASE_ADDR, 1 },
 };
 
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
 	struct fsl_esdhc_cfg *cfg = (struct fsl_esdhc_cfg *)mmc->priv;
+	int ret;
 
 	mxc_request_iomux(MX53_PIN_GPIO_1, IOMUX_CONFIG_ALT1);
 	mxc_request_iomux(MX53_PIN_GPIO_4, IOMUX_CONFIG_ALT1);
 
 	if (cfg->esdhc_base == MMC_SDHC1_BASE_ADDR)
-		*cd = gpio_get_value(1); /*GPIO1_1*/
+		ret = !gpio_get_value(1); /* GPIO1_1 */
 	else
-		*cd = gpio_get_value(4); /*GPIO1_4*/
+		ret = !gpio_get_value(4); /* GPIO1_4 */
 
-	return 0;
+	return ret;
 }
 
 int board_mmc_init(bd_t *bis)

board/freescale/mx53evk/mx53evk.c

@@ -208,19 +208,20 @@ struct fsl_esdhc_cfg esdhc_cfg[2] = {
 	{MMC_SDHC3_BASE_ADDR, 1},
 };
 
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
 	struct fsl_esdhc_cfg *cfg = (struct fsl_esdhc_cfg *)mmc->priv;
+	int ret;
 
 	mxc_request_iomux(MX53_PIN_EIM_DA11, IOMUX_CONFIG_ALT1);
 	mxc_request_iomux(MX53_PIN_EIM_DA13, IOMUX_CONFIG_ALT1);
 
 	if (cfg->esdhc_base == MMC_SDHC1_BASE_ADDR)
-		*cd = gpio_get_value(77); /*GPIO3_13*/
+		ret = !gpio_get_value(77); /* GPIO3_13 */
 	else
-		*cd = gpio_get_value(75); /*GPIO3_11*/
+		ret = !gpio_get_value(75); /* GPIO3_11 */
 
-	return 0;
+	return ret;
 }
 
 int board_mmc_init(bd_t *bis)

board/freescale/mx53loco/mx53loco.c

@@ -147,19 +147,20 @@ struct fsl_esdhc_cfg esdhc_cfg[2] = {
 	{MMC_SDHC3_BASE_ADDR, 1},
 };
 
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
 	struct fsl_esdhc_cfg *cfg = (struct fsl_esdhc_cfg *)mmc->priv;
+	int ret;
 
 	mxc_request_iomux(MX53_PIN_EIM_DA11, IOMUX_CONFIG_ALT1);
 	mxc_request_iomux(MX53_PIN_EIM_DA13, IOMUX_CONFIG_ALT1);
 
 	if (cfg->esdhc_base == MMC_SDHC1_BASE_ADDR)
-		*cd = gpio_get_value(77); /*GPIO3_13*/
+		ret = !gpio_get_value(77); /* GPIO3_13 */
 	else
-		*cd = gpio_get_value(75); /*GPIO3_11*/
+		ret = !gpio_get_value(75); /* GPIO3_11 */
 
-	return 0;
+	return ret;
 }
 
 int board_mmc_init(bd_t *bis)

board/freescale/mx53smd/mx53smd.c

@@ -132,12 +132,10 @@ struct fsl_esdhc_cfg esdhc_cfg[1] = {
 	{MMC_SDHC1_BASE_ADDR, 1},
 };
 
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
 	mxc_request_iomux(MX53_PIN_EIM_DA13, IOMUX_CONFIG_ALT1);
-	*cd = gpio_get_value(77); /*GPIO3_13*/
-
-	return 0;
+	return !gpio_get_value(77); /* GPIO3_13 */
 }
 
 int board_mmc_init(bd_t *bis)

doc/README.atmel_mci

@@ -59,17 +59,9 @@ int board_mmc_init(bd_t *bd)
 }
 
 /* this is a weak define that we are overriding */
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)
+int board_mmc_getcd(struct mmc *mmc)
 {
-	/*
-	 * the only currently existing use of this function
-	 * (fsl_esdhc.c) suggests this function must return
-	 * *cs = TRUE if a card is NOT detected -> in most
-	 * cases the value of the pin when the detect switch
-	 * closes to GND
-	 */
-	*cd = at91_get_gpio_value (CONFIG_SYS_MMC_CD_PIN) ? 1 : 0;
-	return 0;
+	return !at91_get_gpio_value(CONFIG_SYS_MMC_CD_PIN);
 }
 
 #endif

drivers/mmc/fsl_esdhc.c

@@ -419,7 +419,6 @@ static int esdhc_init(struct mmc *mmc)
 	struct fsl_esdhc *regs = (struct fsl_esdhc *)cfg->esdhc_base;
 	int timeout = 1000;
 	int ret = 0;
-	u8 card_absent;
 
 	/* Reset the entire host controller */
 	esdhc_write32(&regs->sysctl, SYSCTL_RSTA);
@@ -447,7 +446,8 @@ static int esdhc_init(struct mmc *mmc)
 	esdhc_clrsetbits32(&regs->sysctl, SYSCTL_TIMEOUT_MASK, 14 << 16);
 
 	/* Check if there is a callback for detecting the card */
-	if (board_mmc_getcd(&card_absent, mmc)) {
+	ret = board_mmc_getcd(mmc);
+	if (ret < 0) {
 		timeout = 1000;
 		while (!(esdhc_read32(&regs->prsstat) & PRSSTAT_CINS) &&
 				--timeout)
@@ -456,8 +456,10 @@ static int esdhc_init(struct mmc *mmc)
 		if (timeout <= 0)
 			ret = NO_CARD_ERR;
 	} else {
-		if (card_absent)
+		if (ret == 0)
 			ret = NO_CARD_ERR;
+		else
+			ret = 0;
 	}
 
 	return ret;

drivers/mmc/mmc.c

@@ -40,11 +40,11 @@
 static struct list_head mmc_devices;
 static int cur_dev_num = -1;
 
-int __board_mmc_getcd(u8 *cd, struct mmc *mmc) {
+int __board_mmc_getcd(struct mmc *mmc) {
 	return -1;
 }
 
-int board_mmc_getcd(u8 *cd, struct mmc *mmc)__attribute__((weak,
+int board_mmc_getcd(struct mmc *mmc)__attribute__((weak,
 	alias("__board_mmc_getcd")));
 
 int mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)

include/mmc.h

@@ -314,7 +314,7 @@ struct mmc *find_mmc_device(int dev_num);
 int mmc_set_dev(int dev_num);
 void print_mmc_devices(char separator);
 int get_mmc_num(void);
-int board_mmc_getcd(u8 *cd, struct mmc *mmc);
+int board_mmc_getcd(struct mmc *mmc);
 int mmc_switch_part(int dev_num, unsigned int part_num);
 
 #ifdef CONFIG_GENERIC_MMC