diff options
Diffstat (limited to 'drivers/mmc/core/core.c')
-rw-r--r-- | drivers/mmc/core/core.c | 246 |
1 files changed, 219 insertions, 27 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index aaed7687cf0..08a3cf2a761 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -319,11 +319,45 @@ out: } EXPORT_SYMBOL(mmc_start_bkops); +/* + * mmc_wait_data_done() - done callback for data request + * @mrq: done data request + * + * Wakes up mmc context, passed as a callback to host controller driver + */ +static void mmc_wait_data_done(struct mmc_request *mrq) +{ + mrq->host->context_info.is_done_rcv = true; + wake_up_interruptible(&mrq->host->context_info.wait); +} + static void mmc_wait_done(struct mmc_request *mrq) { complete(&mrq->completion); } +/* + *__mmc_start_data_req() - starts data request + * @host: MMC host to start the request + * @mrq: data request to start + * + * Sets the done callback to be called when request is completed by the card. + * Starts data mmc request execution + */ +static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq) +{ + mrq->done = mmc_wait_data_done; + mrq->host = host; + if (mmc_card_removed(host->card)) { + mrq->cmd->error = -ENOMEDIUM; + mmc_wait_data_done(mrq); + return -ENOMEDIUM; + } + mmc_start_request(host, mrq); + + return 0; +} + static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq) { init_completion(&mrq->completion); @@ -337,6 +371,62 @@ static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq) return 0; } +/* + * mmc_wait_for_data_req_done() - wait for request completed + * @host: MMC host to prepare the command. + * @mrq: MMC request to wait for + * + * Blocks MMC context till host controller will ack end of data request + * execution or new request notification arrives from the block layer. + * Handles command retries. + * + * Returns enum mmc_blk_status after checking errors. + */ +static int mmc_wait_for_data_req_done(struct mmc_host *host, + struct mmc_request *mrq, + struct mmc_async_req *next_req) +{ + struct mmc_command *cmd; + struct mmc_context_info *context_info = &host->context_info; + int err; + unsigned long flags; + + while (1) { + wait_event_interruptible(context_info->wait, + (context_info->is_done_rcv || + context_info->is_new_req)); + spin_lock_irqsave(&context_info->lock, flags); + context_info->is_waiting_last_req = false; + spin_unlock_irqrestore(&context_info->lock, flags); + if (context_info->is_done_rcv) { + context_info->is_done_rcv = false; + context_info->is_new_req = false; + cmd = mrq->cmd; + if (!cmd->error || !cmd->retries || + mmc_card_removed(host->card)) { + err = host->areq->err_check(host->card, + host->areq); + break; /* return err */ + } else { + pr_info("%s: req failed (CMD%u): %d, retrying...\n", + mmc_hostname(host), + cmd->opcode, cmd->error); + cmd->retries--; + cmd->error = 0; + host->ops->request(host, mrq); + continue; /* wait for done/new event again */ + } + } else if (context_info->is_new_req) { + context_info->is_new_req = false; + if (!next_req) { + err = MMC_BLK_NEW_REQUEST; + break; /* return err */ + } + } + } + return err; +} + static void mmc_wait_for_req_done(struct mmc_host *host, struct mmc_request *mrq) { @@ -426,8 +516,16 @@ struct mmc_async_req *mmc_start_req(struct mmc_host *host, mmc_pre_req(host, areq->mrq, !host->areq); if (host->areq) { - mmc_wait_for_req_done(host, host->areq->mrq); - err = host->areq->err_check(host->card, host->areq); + err = mmc_wait_for_data_req_done(host, host->areq->mrq, areq); + if (err == MMC_BLK_NEW_REQUEST) { + if (error) + *error = err; + /* + * The previous request was not completed, + * nothing to return + */ + return NULL; + } /* * Check BKOPS urgency for each R1 response */ @@ -439,14 +537,14 @@ struct mmc_async_req *mmc_start_req(struct mmc_host *host, } if (!err && areq) - start_err = __mmc_start_req(host, areq->mrq); + start_err = __mmc_start_data_req(host, areq->mrq); if (host->areq) mmc_post_req(host, host->areq->mrq, 0); /* Cancel a prepared request if it was not started. */ if ((err || start_err) && areq) - mmc_post_req(host, areq->mrq, -EINVAL); + mmc_post_req(host, areq->mrq, -EINVAL); if (err) host->areq = NULL; @@ -1137,7 +1235,7 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, */ voltage = regulator_get_voltage(supply); - if (regulator_count_voltages(supply) == 1) + if (!regulator_can_change_voltage(supply)) min_uV = max_uV = voltage; if (voltage < 0) @@ -1219,10 +1317,30 @@ u32 mmc_select_voltage(struct mmc_host *host, u32 ocr) return ocr; } -int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage, bool cmd11) +int __mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage) +{ + int err = 0; + int old_signal_voltage = host->ios.signal_voltage; + + host->ios.signal_voltage = signal_voltage; + if (host->ops->start_signal_voltage_switch) { + mmc_host_clk_hold(host); + err = host->ops->start_signal_voltage_switch(host, &host->ios); + mmc_host_clk_release(host); + } + + if (err) + host->ios.signal_voltage = old_signal_voltage; + + return err; + +} + +int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage) { struct mmc_command cmd = {0}; int err = 0; + u32 clock; BUG_ON(!host); @@ -1230,27 +1348,81 @@ int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage, bool cmd11 * Send CMD11 only if the request is to switch the card to * 1.8V signalling. */ - if ((signal_voltage != MMC_SIGNAL_VOLTAGE_330) && cmd11) { - cmd.opcode = SD_SWITCH_VOLTAGE; - cmd.arg = 0; - cmd.flags = MMC_RSP_R1 | MMC_CMD_AC; + if (signal_voltage == MMC_SIGNAL_VOLTAGE_330) + return __mmc_set_signal_voltage(host, signal_voltage); - err = mmc_wait_for_cmd(host, &cmd, 0); - if (err) - return err; + /* + * If we cannot switch voltages, return failure so the caller + * can continue without UHS mode + */ + if (!host->ops->start_signal_voltage_switch) + return -EPERM; + if (!host->ops->card_busy) + pr_warning("%s: cannot verify signal voltage switch\n", + mmc_hostname(host)); + + cmd.opcode = SD_SWITCH_VOLTAGE; + cmd.arg = 0; + cmd.flags = MMC_RSP_R1 | MMC_CMD_AC; - if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR)) - return -EIO; + err = mmc_wait_for_cmd(host, &cmd, 0); + if (err) + return err; + + if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR)) + return -EIO; + + mmc_host_clk_hold(host); + /* + * The card should drive cmd and dat[0:3] low immediately + * after the response of cmd11, but wait 1 ms to be sure + */ + mmc_delay(1); + if (host->ops->card_busy && !host->ops->card_busy(host)) { + err = -EAGAIN; + goto power_cycle; } + /* + * During a signal voltage level switch, the clock must be gated + * for 5 ms according to the SD spec + */ + clock = host->ios.clock; + host->ios.clock = 0; + mmc_set_ios(host); - host->ios.signal_voltage = signal_voltage; + if (__mmc_set_signal_voltage(host, signal_voltage)) { + /* + * Voltages may not have been switched, but we've already + * sent CMD11, so a power cycle is required anyway + */ + err = -EAGAIN; + goto power_cycle; + } - if (host->ops->start_signal_voltage_switch) { - mmc_host_clk_hold(host); - err = host->ops->start_signal_voltage_switch(host, &host->ios); - mmc_host_clk_release(host); + /* Keep clock gated for at least 5 ms */ + mmc_delay(5); + host->ios.clock = clock; + mmc_set_ios(host); + + /* Wait for at least 1 ms according to spec */ + mmc_delay(1); + + /* + * Failure to switch is indicated by the card holding + * dat[0:3] low + */ + if (host->ops->card_busy && host->ops->card_busy(host)) + err = -EAGAIN; + +power_cycle: + if (err) { + pr_debug("%s: Signal voltage switch failed, " + "power cycling card\n", mmc_hostname(host)); + mmc_power_cycle(host); } + mmc_host_clk_release(host); + return err; } @@ -1314,7 +1486,7 @@ static void mmc_power_up(struct mmc_host *host) mmc_set_ios(host); /* Set signal voltage to 3.3V */ - mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, false); + __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330); /* * This delay should be sufficient to allow the power supply @@ -1372,6 +1544,14 @@ void mmc_power_off(struct mmc_host *host) mmc_host_clk_release(host); } +void mmc_power_cycle(struct mmc_host *host) +{ + mmc_power_off(host); + /* Wait at least 1 ms according to SD spec */ + mmc_delay(1); + mmc_power_up(host); +} + /* * Cleanup when the last reference to the bus operator is dropped. */ @@ -2388,6 +2568,7 @@ EXPORT_SYMBOL(mmc_flush_cache); * Turn the cache ON/OFF. * Turning the cache OFF shall trigger flushing of the data * to the non-volatile storage. + * This function should be called with host claimed */ int mmc_cache_ctrl(struct mmc_host *host, u8 enable) { @@ -2399,7 +2580,6 @@ int mmc_cache_ctrl(struct mmc_host *host, u8 enable) mmc_card_is_removable(host)) return err; - mmc_claim_host(host); if (card && mmc_card_mmc(card) && (card->ext_csd.cache_size > 0)) { enable = !!enable; @@ -2417,7 +2597,6 @@ int mmc_cache_ctrl(struct mmc_host *host, u8 enable) card->ext_csd.cache_ctrl = enable; } } - mmc_release_host(host); return err; } @@ -2436,10 +2615,6 @@ int mmc_suspend_host(struct mmc_host *host) cancel_delayed_work(&host->detect); mmc_flush_scheduled_work(); - err = mmc_cache_ctrl(host, 0); - if (err) - goto out; - mmc_bus_get(host); if (host->bus_ops && !host->bus_dead) { if (host->bus_ops->suspend) { @@ -2581,6 +2756,23 @@ int mmc_pm_notify(struct notifier_block *notify_block, } #endif +/** + * mmc_init_context_info() - init synchronization context + * @host: mmc host + * + * Init struct context_info needed to implement asynchronous + * request mechanism, used by mmc core, host driver and mmc requests + * supplier. + */ +void mmc_init_context_info(struct mmc_host *host) +{ + spin_lock_init(&host->context_info.lock); + host->context_info.is_new_req = false; + host->context_info.is_done_rcv = false; + host->context_info.is_waiting_last_req = false; + init_waitqueue_head(&host->context_info.wait); +} + static int __init mmc_init(void) { int ret; |