diff options
-rw-r--r-- | drivers/mmc/core/sd.c | 136 | ||||
-rw-r--r-- | include/linux/mmc/sd.h | 1 |
2 files changed, 134 insertions, 3 deletions
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index 0b882aaedf78..bd40c682d264 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -66,6 +66,13 @@ static const unsigned int sd_au_size[] = { __res & __mask; \ }) +#define SD_POWEROFF_NOTIFY_TIMEOUT_MS 2000 + +struct sd_busy_data { + struct mmc_card *card; + u8 *reg_buf; +}; + /* * Given the decoded CSD structure, decode the raw CID to our CID structure. */ @@ -996,6 +1003,66 @@ static bool mmc_sd_card_using_v18(struct mmc_card *card) (SD_MODE_UHS_SDR50 | SD_MODE_UHS_SDR104 | SD_MODE_UHS_DDR50); } +static int sd_write_ext_reg(struct mmc_card *card, u8 fno, u8 page, u16 offset, + u8 reg_data) +{ + struct mmc_host *host = card->host; + struct mmc_request mrq = {}; + struct mmc_command cmd = {}; + struct mmc_data data = {}; + struct scatterlist sg; + u8 *reg_buf; + + reg_buf = kzalloc(512, GFP_KERNEL); + if (!reg_buf) + return -ENOMEM; + + mrq.cmd = &cmd; + mrq.data = &data; + + /* + * Arguments of CMD49: + * [31:31] MIO (0 = memory). + * [30:27] FNO (function number). + * [26:26] MW - mask write mode (0 = disable). + * [25:18] page number. + * [17:9] offset address. + * [8:0] length (0 = 1 byte). + */ + cmd.arg = fno << 27 | page << 18 | offset << 9; + + /* The first byte in the buffer is the data to be written. */ + reg_buf[0] = reg_data; + + data.flags = MMC_DATA_WRITE; + data.blksz = 512; + data.blocks = 1; + data.sg = &sg; + data.sg_len = 1; + sg_init_one(&sg, reg_buf, 512); + + cmd.opcode = SD_WRITE_EXTR_SINGLE; + cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC; + + mmc_set_data_timeout(&data, card); + mmc_wait_for_req(host, &mrq); + + kfree(reg_buf); + + /* + * Note that, the SD card is allowed to signal busy on DAT0 up to 1s + * after the CMD49. Although, let's leave this to be managed by the + * caller. + */ + + if (cmd.error) + return cmd.error; + if (data.error) + return data.error; + + return 0; +} + static int sd_read_ext_reg(struct mmc_card *card, u8 fno, u8 page, u16 offset, u16 len, u8 *reg_buf) { @@ -1446,21 +1513,84 @@ static void mmc_sd_detect(struct mmc_host *host) } } +static int sd_can_poweroff_notify(struct mmc_card *card) +{ + return card->ext_power.feature_support & SD_EXT_POWER_OFF_NOTIFY; +} + +static int sd_busy_poweroff_notify_cb(void *cb_data, bool *busy) +{ + struct sd_busy_data *data = cb_data; + struct mmc_card *card = data->card; + int err; + + /* + * Read the status register for the power management function. It's at + * one byte offset and is one byte long. The Power Off Notification + * Ready is bit 0. + */ + err = sd_read_ext_reg(card, card->ext_power.fno, card->ext_power.page, + card->ext_power.offset + 1, 1, data->reg_buf); + if (err) { + pr_warn("%s: error %d reading status reg of PM func\n", + mmc_hostname(card->host), err); + return err; + } + + *busy = !(data->reg_buf[0] & BIT(0)); + return 0; +} + +static int sd_poweroff_notify(struct mmc_card *card) +{ + struct sd_busy_data cb_data; + u8 *reg_buf; + int err; + + reg_buf = kzalloc(512, GFP_KERNEL); + if (!reg_buf) + return -ENOMEM; + + /* + * Set the Power Off Notification bit in the power management settings + * register at 2 bytes offset. + */ + err = sd_write_ext_reg(card, card->ext_power.fno, card->ext_power.page, + card->ext_power.offset + 2, BIT(0)); + if (err) { + pr_warn("%s: error %d writing Power Off Notify bit\n", + mmc_hostname(card->host), err); + goto out; + } + + cb_data.card = card; + cb_data.reg_buf = reg_buf; + err = __mmc_poll_for_busy(card, SD_POWEROFF_NOTIFY_TIMEOUT_MS, + &sd_busy_poweroff_notify_cb, &cb_data); + +out: + kfree(reg_buf); + return err; +} + static int _mmc_sd_suspend(struct mmc_host *host) { + struct mmc_card *card = host->card; int err = 0; mmc_claim_host(host); - if (mmc_card_suspended(host->card)) + if (mmc_card_suspended(card)) goto out; - if (!mmc_host_is_spi(host)) + if (sd_can_poweroff_notify(card)) + err = sd_poweroff_notify(card); + else if (!mmc_host_is_spi(host)) err = mmc_deselect_cards(host); if (!err) { mmc_power_off(host); - mmc_card_set_suspended(host->card); + mmc_card_set_suspended(card); } out: diff --git a/include/linux/mmc/sd.h b/include/linux/mmc/sd.h index 43bfc5c39ad4..6727576a8755 100644 --- a/include/linux/mmc/sd.h +++ b/include/linux/mmc/sd.h @@ -31,6 +31,7 @@ /* class 11 */ #define SD_READ_EXTR_SINGLE 48 /* adtc [31:0] R1 */ +#define SD_WRITE_EXTR_SINGLE 49 /* adtc [31:0] R1 */ /* OCR bit definitions */ #define SD_OCR_S18R (1 << 24) /* 1.8V switching request */ |