[PATCH v4 03/12] omap_hsmmc: add support for pre_req and post_req

From: Per Forlin
Date: Wed May 25 2011 - 18:01:00 EST


pre_req() runs dma_map_sg(), post_req() runs dma_unmap_sg.
If not calling pre_req() before omap_hsmmc_request()
dma_map_sg will be issued before starting the transfer.
It is optional to use pre_req(). If issuing pre_req()
post_req() must be to be called as well.

Signed-off-by: Per Forlin <per.forlin@xxxxxxxxxx>
---
drivers/mmc/host/omap_hsmmc.c | 87 +++++++++++++++++++++++++++++++++++++++--
1 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index ad3731a..2116c09 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -141,6 +141,11 @@
#define OMAP_HSMMC_WRITE(base, reg, val) \
__raw_writel((val), (base) + OMAP_HSMMC_##reg)

+struct omap_hsmmc_next {
+ unsigned int dma_len;
+ s32 cookie;
+};
+
struct omap_hsmmc_host {
struct device *dev;
struct mmc_host *mmc;
@@ -184,6 +189,7 @@ struct omap_hsmmc_host {
int reqs_blocked;
int use_reg;
int req_in_progress;
+ struct omap_hsmmc_next next_data;

struct omap_mmc_platform_data *pdata;
};
@@ -1344,8 +1350,9 @@ static void omap_hsmmc_dma_cb(int lch, u16 ch_status, void *cb_data)
return;
}

- dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
- omap_hsmmc_get_dma_dir(host, data));
+ if (!data->host_cookie)
+ dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+ omap_hsmmc_get_dma_dir(host, data));

req_in_progress = host->req_in_progress;
dma_ch = host->dma_ch;
@@ -1363,6 +1370,45 @@ static void omap_hsmmc_dma_cb(int lch, u16 ch_status, void *cb_data)
}
}

+static int omap_hsmmc_pre_dma_transfer(struct omap_hsmmc_host *host,
+ struct mmc_data *data,
+ struct omap_hsmmc_next *next)
+{
+ int dma_len;
+
+ if (!next && data->host_cookie &&
+ data->host_cookie != host->next_data.cookie) {
+ printk(KERN_WARNING "[%s] invalid cookie: data->host_cookie %d"
+ " host->next_data.cookie %d\n",
+ __func__, data->host_cookie, host->next_data.cookie);
+ data->host_cookie = 0;
+ }
+
+ /* Check if next job is already prepared */
+ if (next ||
+ (!next && data->host_cookie != host->next_data.cookie)) {
+ dma_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
+ data->sg_len,
+ omap_hsmmc_get_dma_dir(host, data));
+
+ } else {
+ dma_len = host->next_data.dma_len;
+ host->next_data.dma_len = 0;
+ }
+
+
+ if (dma_len == 0)
+ return -EINVAL;
+
+ if (next) {
+ next->dma_len = dma_len;
+ data->host_cookie = ++next->cookie < 0 ? 1 : next->cookie;
+ } else
+ host->dma_len = dma_len;
+
+ return 0;
+}
+
/*
* Routine to configure and start DMA for the MMC card
*/
@@ -1396,9 +1442,10 @@ static int omap_hsmmc_start_dma_transfer(struct omap_hsmmc_host *host,
mmc_hostname(host->mmc), ret);
return ret;
}
+ ret = omap_hsmmc_pre_dma_transfer(host, data, NULL);
+ if (ret)
+ return ret;

- host->dma_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
- data->sg_len, omap_hsmmc_get_dma_dir(host, data));
host->dma_ch = dma_ch;
host->dma_sg_idx = 0;

@@ -1478,6 +1525,35 @@ omap_hsmmc_prepare_data(struct omap_hsmmc_host *host, struct mmc_request *req)
return 0;
}

+static void omap_hsmmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
+ int err)
+{
+ struct omap_hsmmc_host *host = mmc_priv(mmc);
+ struct mmc_data *data = mrq->data;
+
+ if (host->use_dma) {
+ dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+ omap_hsmmc_get_dma_dir(host, data));
+ data->host_cookie = 0;
+ }
+}
+
+static void omap_hsmmc_pre_req(struct mmc_host *mmc, struct mmc_request *mrq,
+ bool is_first_req)
+{
+ struct omap_hsmmc_host *host = mmc_priv(mmc);
+
+ if (mrq->data->host_cookie) {
+ mrq->data->host_cookie = 0;
+ return ;
+ }
+
+ if (host->use_dma)
+ if (omap_hsmmc_pre_dma_transfer(host, mrq->data,
+ &host->next_data))
+ mrq->data->host_cookie = 0;
+}
+
/*
* Request function. for read/write operation
*/
@@ -1926,6 +2002,8 @@ static int omap_hsmmc_disable_fclk(struct mmc_host *mmc, int lazy)
static const struct mmc_host_ops omap_hsmmc_ops = {
.enable = omap_hsmmc_enable_fclk,
.disable = omap_hsmmc_disable_fclk,
+ .post_req = omap_hsmmc_post_req,
+ .pre_req = omap_hsmmc_pre_req,
.request = omap_hsmmc_request,
.set_ios = omap_hsmmc_set_ios,
.get_cd = omap_hsmmc_get_cd,
@@ -2075,6 +2153,7 @@ static int __init omap_hsmmc_probe(struct platform_device *pdev)
host->mapbase = res->start;
host->base = ioremap(host->mapbase, SZ_4K);
host->power_mode = MMC_POWER_OFF;
+ host->next_data.cookie = 1;

platform_set_drvdata(pdev, host);
INIT_WORK(&host->mmc_carddetect_work, omap_hsmmc_detect);
--
1.7.4.1

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