This patch supplies a card reset rountine for device driver to recover
the SDIO card when some error occurs in hardware.
Signed-off-by: JiebingLi <[email protected]>
---
drivers/mmc/core/sdio.c | 182 +++++++++++++++++++++++++++++++++++++++++
include/linux/mmc/sdio_func.h | 4 +
2 files changed, 186 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index fb99ccf..ce74bda 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -24,6 +24,8 @@
#include "sdio_ops.h"
#include "sdio_cis.h"
+#define to_sdio_driver(d) container_of(d, struct sdio_driver, drv)
+
static int sdio_read_fbr(struct sdio_func *func)
{
int ret;
@@ -439,3 +441,183 @@ err:
return err;
}
+/*
+ * Handle the re-initialization of a SDIO card.
+ */
+static int mmc_sdio_reinit_card(struct mmc_host *host,
+ struct mmc_card *oldcard)
+{
+ int err = 0;
+ u32 ocr;
+ struct mmc_card *card;
+
+ BUG_ON(!host);
+ WARN_ON(!host->claimed);
+
+ if (!oldcard)
+ goto err;
+
+ card = oldcard;
+
+ err = mmc_send_io_op_cond(host, 0, &ocr);
+ if (err)
+ goto remove;
+
+ /*
+ * Inform the card of the voltage
+ */
+ err = mmc_send_io_op_cond(host, host->ocr, &ocr);
+ if (err)
+ goto remove;
+
+ /*
+ * For SPI, enable CRC as appropriate.
+ */
+ if (mmc_host_is_spi(host)) {
+ err = mmc_spi_set_crc(host, use_spi_crc);
+ if (err)
+ goto remove;
+ }
+
+ if (!mmc_host_is_spi(host)) {
+ err = mmc_send_relative_addr(host, &card->rca);
+ if (err)
+ goto remove;
+
+ mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
+ }
+
+ /*
+ * Select card, as all following commands rely on that.
+ */
+ if (!mmc_host_is_spi(host)) {
+ err = mmc_select_card(card);
+ if (err)
+ goto remove;
+ }
+
+ /*
+ * Read the common CIS tuples.
+ */
+ err = sdio_read_cccr(card);
+ if (err)
+ goto remove;
+
+ /*
+ * Switch to high-speed (if supported).
+ */
+ err = sdio_enable_hs(card);
+ if (err)
+ goto remove;
+
+ /*
+ * Change to the card's maximum speed.
+ */
+ if (mmc_card_highspeed(card))
+ mmc_set_clock(host, 50000000);
+ else
+ mmc_set_clock(host, card->cis.max_dtr);
+
+ /*
+ * Switch to wider bus (if supported).
+ */
+ err = sdio_enable_wide(card);
+ if (err)
+ goto remove;
+
+ host->card = card;
+
+ return 0;
+
+remove:
+err:
+ return err;
+}
+
+/*
+ * Sometimes there is a hang in the host interface hardware,
+ * eg: the device driver can not access the device due to some error.
+ * This API is used by device driver to perform a SDIO device
+ * reset in order to solve such issues.
+ *
+ * Warn all device drivers using their pre_reset method,
+ * performs the whole SDIO card and then lets the drivers
+ * know that the reset is over using the post_reset method.
+ */
+int sdio_reset_device(struct mmc_card *card)
+{
+ int ret = 0;
+ int i = 0;
+ u8 reg = 0;
+
+ BUG_ON(!card);
+ BUG_ON(!card->host);
+ BUG_ON(!card->sdio_func);
+
+ if (!mmc_card_present(card)) {
+ dev_dbg(&card->dev, "device reset not allowed\n");
+ return -EINVAL;
+ }
+
+ for (; i < card->sdio_funcs; i++) {
+ struct sdio_func *func = card->sdio_func[i];
+ struct sdio_driver *drv;
+
+ if (func && func->dev.driver) {
+ drv = to_sdio_driver(func->dev.driver);
+ if (drv->pre_reset) {
+ ret = (drv->pre_reset)(func);
+ if (ret)
+ break;
+ }
+ }
+ }
+
+ if (ret)
+ goto err;
+
+ /* reset SDIO card via CMD52 */
+ mmc_claim_host(card->host);
+
+ ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_ABORT, 0, ®);
+
+ if (ret)
+ reg = 0x08;
+ else
+ reg |= 0x08;
+
+ mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_ABORT, reg, NULL);
+
+ /* re-enumerate the device */
+ ret = mmc_sdio_reinit_card(card->host, card);
+
+ mmc_release_host(card->host);
+
+ if (ret)
+ goto err;
+
+ for (i = card->sdio_funcs - 1; i >= 0; i--) {
+ struct sdio_func *func = card->sdio_func[i];
+ struct sdio_driver *drv;
+
+ if (func && func->dev.driver) {
+ drv = to_sdio_driver(func->dev.driver);
+ if (drv->post_reset) {
+ ret = (drv->post_reset)(func);
+ if (ret)
+ break;
+ }
+ }
+ }
+
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ return -EINVAL;
+
+}
+EXPORT_SYMBOL_GPL(sdio_reset_device);
+
diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h
index 451bdfc..90ec007 100644
--- a/include/linux/mmc/sdio_func.h
+++ b/include/linux/mmc/sdio_func.h
@@ -78,6 +78,9 @@ struct sdio_driver {
int (*probe)(struct sdio_func *, const struct sdio_device_id *);
void (*remove)(struct sdio_func *);
+ int (*pre_reset)(struct sdio_func *);
+ int (*post_reset)(struct sdio_func *);
+
struct device_driver drv;
};
@@ -150,5 +153,6 @@ extern unsigned char sdio_f0_readb(struct sdio_func *func,
extern void sdio_f0_writeb(struct sdio_func *func, unsigned char b,
unsigned int addr, int *err_ret);
+extern int sdio_reset_device(struct mmc_card *card);
#endif
--
1.6.0