From 48ef8a2a1e5e6a2a189009e880e341ddb452971d Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Mon, 13 Apr 2020 10:46:04 +0800 Subject: [PATCH] mmc: host: sdhci: Implement the request_atomic() API Implement the request_atomic() ops for the sdhci driver to process one request in the atomic context if the card is nonremovable. Moreover, we should return BUSY flag if controller has not released the inhibit bits to allow HSQ trying to send request again in non-atomic context. Suggested-by: Adrian Hunter Signed-off-by: Baolin Wang Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/9ed34afa9fb42e0c234065cac5401d7826942b55.1586744073.git.baolin.wang7@gmail.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci.c | 34 ++++++++++++++++++++++++++++++++++ drivers/mmc/host/sdhci.h | 1 + 2 files changed, 35 insertions(+) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 153c5fda0645..6cc72177f853 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2144,6 +2144,40 @@ void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq) } EXPORT_SYMBOL_GPL(sdhci_request); +int sdhci_request_atomic(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct sdhci_host *host = mmc_priv(mmc); + struct mmc_command *cmd; + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&host->lock, flags); + + if (sdhci_present_error(host, mrq->cmd, true)) { + sdhci_finish_mrq(host, mrq); + goto out_finish; + } + + cmd = sdhci_manual_cmd23(host, mrq) ? mrq->sbc : mrq->cmd; + + /* + * The HSQ may send a command in interrupt context without polling + * the busy signaling, which means we should return BUSY if controller + * has not released inhibit bits to allow HSQ trying to send request + * again in non-atomic context. So we should not finish this request + * here. + */ + if (!sdhci_send_command(host, cmd)) + ret = -EBUSY; + else + sdhci_led_activate(host); + +out_finish: + spin_unlock_irqrestore(&host->lock, flags); + return ret; +} +EXPORT_SYMBOL_GPL(sdhci_request_atomic); + void sdhci_set_bus_width(struct sdhci_host *host, int width) { u8 ctrl; diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index 8483419a937e..8d2a096fdfb1 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -770,6 +770,7 @@ void sdhci_set_power_and_bus_voltage(struct sdhci_host *host, void sdhci_set_power_noreg(struct sdhci_host *host, unsigned char mode, unsigned short vdd); void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq); +int sdhci_request_atomic(struct mmc_host *mmc, struct mmc_request *mrq); void sdhci_set_bus_width(struct sdhci_host *host, int width); void sdhci_reset(struct sdhci_host *host, u8 mask); void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing); -- GitLab