From: Hans de Goede <hdegoede@redhat.com>
Date: Tue, 22 Sep 2015 15:30:26 +0000 (+0200)
Subject: mmc: sunxi: Add card busy detection
X-Git-Tag: firefly_0821_release~176^2~850^2~51
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c1590dd86d6e34df214f30a501682e392be0ba3c;p=firefly-linux-kernel-4.4.55.git
mmc: sunxi: Add card busy detection
Some sdio wifi modules have not been working reliable with the sunxi-mmc
host code. This turns out to be caused by starting new io-rw commands while
the card signals that it is still busy processing a previous command.
This commit adds card-busy detection to the sunxi-mmc driver which together
with recent core changes to check card-busy before starting io-rw commands
fixes the wifi reliability issues on the Cubietruck and other sunxi boards
using sdio wifi.
Reported-by: Eugene K <sigintmailru@gmail.com>
Suggested-by: Eugene K <sigintmailru@gmail.com>
Cc: Eugene K <sigintmailru@gmail.com>
Cc: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index b981b8552e43..83de82bceafc 100644
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -873,6 +873,13 @@ static void sunxi_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
spin_unlock_irqrestore(&host->lock, iflags);
}
+static int sunxi_mmc_card_busy(struct mmc_host *mmc)
+{
+ struct sunxi_mmc_host *host = mmc_priv(mmc);
+
+ return !!(mmc_readl(host, REG_STAS) & SDXC_CARD_DATA_BUSY);
+}
+
static const struct of_device_id sunxi_mmc_of_match[] = {
{ .compatible = "allwinner,sun4i-a10-mmc", },
{ .compatible = "allwinner,sun5i-a13-mmc", },
@@ -888,6 +895,7 @@ static struct mmc_host_ops sunxi_mmc_ops = {
.get_cd = mmc_gpio_get_cd,
.enable_sdio_irq = sunxi_mmc_enable_sdio_irq,
.hw_reset = sunxi_mmc_hw_reset,
+ .card_busy = sunxi_mmc_card_busy,
};
static const struct sunxi_mmc_clk_delay sunxi_mmc_clk_delays[] = {