[PATCH v3] mmc: davinci: add support for SDIO irq handling

Sekhar Nori
2010-12-30T10:52:37Z

From: Alagu Sankar <alagusankar-LW5URSxhY0VBDgjK7y7TUQ@public.gmane.org>

This patch adds support for handing SDIO interrupt on
DaVinci MMC/SD controller.

The patch has been tested on DM355 and DA850 EVMs with
Marvell Libertas based SDIO wireless LAN card.

Signed-off-by: Alagu Sankar <alagusankar-LW5URSxhY0VBDgjK7y7TUQ@public.gmane.org>
Signed-off-by: Sekhar Nori <nsekhar-l0cyMroinI0@public.gmane.org>
---
Applies to mmc-next branch of the mmc tree

Since v2, the patch has received some cosmetic clean-up and
is being posted for the first time on the linux-mmc list.

drivers/mmc/host/davinci_mmc.c | 78 +++++++++++++++++++++++++++++++++++++---
1 files changed, 73 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index b643dde..04c2fa4 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -66,8 +66,8 @@
#define DAVINCI_MMCBLNC 0x60
#define DAVINCI_SDIOCTL 0x64
#define DAVINCI_SDIOST0 0x68
-#define DAVINCI_SDIOEN 0x6C
-#define DAVINCI_SDIOST 0x70
+#define DAVINCI_SDIOIEN 0x6C
+#define DAVINCI_SDIOIST 0x70
#define DAVINCI_MMCFIFOCTL 0x74 /* FIFO Control Register */

/* DAVINCI_MMCCTL definitions */
@@ -131,6 +131,14 @@
#define MMCFIFOCTL_ACCWD_2 (2 << 3) /* access width of 2 bytes */
#define MMCFIFOCTL_ACCWD_1 (3 << 3) /* access width of 1 byte */

+/* DAVINCI_SDIOST0 definitions */
+#define SDIOST0_DAT1_HI BIT(0)
+
+/* DAVINCI_SDIOIEN definitions */
+#define SDIOIEN_IOINTEN BIT(0)
+
+/* DAVINCI_SDIOIST definitions */
+#define SDIOIST_IOINT BIT(0)

/* MMCSD Init clock in Hz in opendrain mode */
#define MMCSD_INIT_CLOCK 200000
@@ -164,7 +172,7 @@ struct mmc_davinci_host {
unsigned int mmc_input_clk;
void __iomem *base;
struct resource *mem_res;
- int irq;
+ int mmc_irq, sdio_irq;
unsigned char bus_mode;

#define DAVINCI_MMC_DATADIR_NONE 0
@@ -184,6 +192,7 @@ struct mmc_davinci_host {
u32 rxdma, txdma;
bool use_dma;
bool do_dma;
+ bool sdio_int;

/* Scatterlist DMA uses one or more parameter RAM entries:
* the main one (associated with rxdma or txdma) plus zero or
@@ -866,6 +875,19 @@ mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data)
{
host->data = NULL;

+ if (host->mmc->caps & MMC_CAP_SDIO_IRQ) {
+ /*
+ * SDIO Interrupt Detection work-around as suggested by
+ * Davinci Errata (TMS320DM355 Silicon Revision 1.1 Errata
+ * 2.1.6): Signal SDIO interrupt only if it is enabled by core
+ */
+ if (host->sdio_int && !(readl(host->base + DAVINCI_SDIOST0) &
+ SDIOST0_DAT1_HI)) {
+ writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
+ mmc_signal_sdio_irq(host->mmc);
+ }
+ }
+
if (host->do_dma) {
davinci_abort_dma(host);

@@ -932,6 +954,21 @@ davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
mmc_davinci_reset_ctrl(host, 0);
}

+static irqreturn_t mmc_davinci_sdio_irq(int irq, void *dev_id)
+{
+ struct mmc_davinci_host *host = dev_id;
+ unsigned int status;
+
+ status = readl(host->base + DAVINCI_SDIOIST);
+ if (status & SDIOIST_IOINT) {
+ dev_dbg(mmc_dev(host->mmc),
+ "SDIO interrupt status %x\n", status);
+ writel(status | SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
+ mmc_signal_sdio_irq(host->mmc);
+ }
+ return IRQ_HANDLED;
+}
+
static irqreturn_t mmc_davinci_irq(int irq, void *dev_id)
{
struct mmc_davinci_host *host = (struct mmc_davinci_host *)dev_id;
@@ -1076,11 +1113,32 @@ static int mmc_davinci_get_ro(struct mmc_host *mmc)
return config->get_ro(pdev->id);
}

+static void mmc_davinci_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{
+ struct mmc_davinci_host *host = mmc_priv(mmc);
+
+ if (enable) {
+ if (!(readl(host->base + DAVINCI_SDIOST0) & SDIOST0_DAT1_HI)) {
+ writel(SDIOIST_IOINT, host->base + DAVINCI_SDIOIST);
+ mmc_signal_sdio_irq(host->mmc);
+ } else {
+ host->sdio_int = true;
+ writel(readl(host->base + DAVINCI_SDIOIEN) |
+ SDIOIEN_IOINTEN, host->base + DAVINCI_SDIOIEN);
+ }
+ } else {
+ host->sdio_int = false;
+ writel(readl(host->base + DAVINCI_SDIOIEN) & ~SDIOIEN_IOINTEN,
+ host->base + DAVINCI_SDIOIEN);
+ }
+}
+
static struct mmc_host_ops mmc_davinci_ops = {
.request = mmc_davinci_request,
.set_ios = mmc_davinci_set_ios,
.get_cd = mmc_davinci_get_cd,
.get_ro = mmc_davinci_get_ro,
+ .enable_sdio_irq = mmc_davinci_enable_sdio_irq,
};

/*----------------------------------------------------------------------*/
@@ -1209,7 +1267,8 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
host->nr_sg = MAX_NR_SG;

host->use_dma = use_dma;
- host->irq = irq;
+ host->mmc_irq = irq;
+ host->sdio_irq = platform_get_irq(pdev, 1);

if (host->use_dma && davinci_acquire_dma_channels(host) != 0)
host->use_dma = 0;
@@ -1270,6 +1329,13 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
if (ret)
goto out;

+ if (host->sdio_irq != NO_IRQ) {
+ ret = request_irq(host->sdio_irq, mmc_davinci_sdio_irq, 0,
+ mmc_hostname(mmc), host);
+ if (!ret)
+ mmc->caps |= MMC_CAP_SDIO_IRQ;
+ }
+
rename_region(mem, mmc_hostname(mmc));

dev_info(mmc_dev(host->mmc), "Using %s, %d-bit mode\n",
@@ -1313,7 +1379,9 @@ static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
mmc_davinci_cpufreq_deregister(host);

mmc_remove_host(host->mmc);
- free_irq(host->irq, host);
+ free_irq(host->mmc_irq, host);
+ if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
+ free_irq(host->sdio_irq, host);

davinci_release_dma_channels(host);

--
1.7.3.2