[PATCH] mmc: meson-gx: add SDIO interrupt support

[Heiner Kallweit]

This adds SDIO interrupt support.
Successfully tested on a S905X4-based system with a BRCM4334
SDIO wifi module (brcmfmac driver).

Signed-off-by: Heiner Kallweit <hkallweit1 at gmail.com>
---
 drivers/mmc/host/meson-gx-mmc.c | 45 +++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index 2f08d442e..e8d53fcdd 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -41,14 +41,17 @@
 #define   CLK_V2_TX_DELAY_MASK GENMASK(19, 16)
 #define   CLK_V2_RX_DELAY_MASK GENMASK(23, 20)
 #define   CLK_V2_ALWAYS_ON BIT(24)
+#define   CLK_V2_IRQ_SDIO_SLEEP BIT(29)
 
 #define   CLK_V3_TX_DELAY_MASK GENMASK(21, 16)
 #define   CLK_V3_RX_DELAY_MASK GENMASK(27, 22)
 #define   CLK_V3_ALWAYS_ON BIT(28)
+#define   CLK_V3_IRQ_SDIO_SLEEP BIT(29)
 
 #define   CLK_TX_DELAY_MASK(h)		(h->data->tx_delay_mask)
 #define   CLK_RX_DELAY_MASK(h)		(h->data->rx_delay_mask)
 #define   CLK_ALWAYS_ON(h)		(h->data->always_on)
+#define   CLK_IRQ_SDIO_SLEEP(h)		(h->data->irq_sdio_sleep)
 
 #define SD_EMMC_DELAY 0x4
 #define SD_EMMC_ADJUST 0x8
@@ -100,9 +103,6 @@
 #define   IRQ_END_OF_CHAIN BIT(13)
 #define   IRQ_RESP_STATUS BIT(14)
 #define   IRQ_SDIO BIT(15)
-#define   IRQ_EN_MASK \
-	(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN | IRQ_RESP_STATUS |\
-	 IRQ_SDIO)
 
 #define SD_EMMC_CMD_CFG 0x50
 #define SD_EMMC_CMD_ARG 0x54
@@ -136,6 +136,7 @@ struct meson_mmc_data {
 	unsigned int rx_delay_mask;
 	unsigned int always_on;
 	unsigned int adjust;
+	unsigned int irq_sdio_sleep;
 };
 
 struct sd_emmc_desc {
@@ -431,6 +432,7 @@ static int meson_mmc_clk_init(struct meson_host *host)
 	clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, CLK_PHASE_180);
 	clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, CLK_PHASE_0);
 	clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, CLK_PHASE_0);
+	clk_reg |= CLK_IRQ_SDIO_SLEEP(host);
 	writel(clk_reg, host->regs + SD_EMMC_CLOCK);
 
 	/* get the mux parents */
@@ -933,7 +935,6 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
 {
 	struct meson_host *host = dev_id;
 	struct mmc_command *cmd;
-	struct mmc_data *data;
 	u32 irq_en, status, raw_status;
 	irqreturn_t ret = IRQ_NONE;
 
@@ -948,14 +949,24 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
 		return IRQ_NONE;
 	}
 
-	if (WARN_ON(!host) || WARN_ON(!host->cmd))
+	if (WARN_ON(!host))
 		return IRQ_NONE;
 
 	/* ack all raised interrupts */
 	writel(status, host->regs + SD_EMMC_STATUS);
 
 	cmd = host->cmd;
-	data = cmd->data;
+
+	if (status & IRQ_SDIO) {
+		mmc_signal_sdio_irq(host->mmc);
+		status &= ~IRQ_SDIO;
+		if (!status)
+			return IRQ_HANDLED;
+	}
+
+	if (WARN_ON(!cmd))
+		return IRQ_NONE;
+
 	cmd->error = 0;
 	if (status & IRQ_CRC_ERR) {
 		dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status);
@@ -973,12 +984,9 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
 
 	meson_mmc_read_resp(host->mmc, cmd);
 
-	if (status & IRQ_SDIO) {
-		dev_dbg(host->dev, "IRQ: SDIO TODO.\n");
-		ret = IRQ_HANDLED;
-	}
-
 	if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
+		struct mmc_data *data = cmd->data;
+
 		if (data && !cmd->error)
 			data->bytes_xfered = data->blksz * data->blocks;
 		if (meson_mmc_bounce_buf_read(data) ||
@@ -1121,6 +1129,18 @@ static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
 	return -EINVAL;
 }
 
+static void meson_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{
+	struct meson_host *host = mmc_priv(mmc);
+	u32 reg_irqen;
+
+	reg_irqen = readl(host->regs + SD_EMMC_IRQ_EN);
+	reg_irqen &= ~IRQ_SDIO;
+	if (enable)
+		reg_irqen |= IRQ_SDIO;
+	writel(reg_irqen, host->regs + SD_EMMC_IRQ_EN);
+}
+
 static const struct mmc_host_ops meson_mmc_ops = {
 	.request	= meson_mmc_request,
 	.set_ios	= meson_mmc_set_ios,
@@ -1130,6 +1150,7 @@ static const struct mmc_host_ops meson_mmc_ops = {
 	.execute_tuning = meson_mmc_resampling_tuning,
 	.card_busy	= meson_mmc_card_busy,
 	.start_signal_voltage_switch = meson_mmc_voltage_switch,
+	.enable_sdio_irq = meson_mmc_enable_sdio_irq,
 };
 
 static int meson_mmc_probe(struct platform_device *pdev)
@@ -1326,6 +1347,7 @@ static const struct meson_mmc_data meson_gx_data = {
 	.rx_delay_mask	= CLK_V2_RX_DELAY_MASK,
 	.always_on	= CLK_V2_ALWAYS_ON,
 	.adjust		= SD_EMMC_ADJUST,
+	.irq_sdio_sleep	= CLK_V2_IRQ_SDIO_SLEEP,
 };
 
 static const struct meson_mmc_data meson_axg_data = {
@@ -1333,6 +1355,7 @@ static const struct meson_mmc_data meson_axg_data = {
 	.rx_delay_mask	= CLK_V3_RX_DELAY_MASK,
 	.always_on	= CLK_V3_ALWAYS_ON,
 	.adjust		= SD_EMMC_V3_ADJUST,
+	.irq_sdio_sleep	= CLK_V3_IRQ_SDIO_SLEEP,
 };
 
 static const struct of_device_id meson_mmc_of_match[] = {
-- 
2.37.2