MMC defines a number of standard DT bindings. Having each driver parse
them individually adds code redundancy and is error prone. Provide a
standard function to unify the parsing. After all drivers are converted
to using it instead of their own parsers, this function can be integrated
into mmc_alloc_host().
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
---
v3: updated to match v3 of mmc.txt disambiguation in patch 02/13.
drivers/mmc/core/host.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++
include/linux/mmc/host.h | 1 +
2 files changed, 91 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index ee2e16b..c412612 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -15,6 +15,8 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/idr.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
#include <linux/pagemap.h>
#include <linux/export.h>
#include <linux/leds.h>
@@ -23,6 +25,7 @@
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
+#include <linux/mmc/slot-gpio.h>
#include "core.h"
#include "host.h"
@@ -294,6 +297,93 @@ static inline void mmc_host_clk_sysfs_init(struct mmc_host *host)
#endif
+void mmc_of_parse(struct mmc_host *host)
+{
+ struct device_node *np;
+ u32 bus_width;
+ bool explicit_inv_wp, gpio_inv_wp = false;
+ enum of_gpio_flags flags;
+ int len, ret, gpio;
+
+ if (!host->parent || !host->parent->of_node)
+ return;
+
+ np = host->parent->of_node;
+
+ if (of_property_read_u32_array(np, "bus-width", &bus_width, 1) < 0) {
+ dev_err(host->parent,
+ "Compulsory \"bus-width\" property is missing!\n");
+ return;
+ }
+
+ switch (bus_width) {
+ case 8:
+ host->caps |= MMC_CAP_8_BIT_DATA;
+ /* Hosts, capable of 8-bit transfers can also do 4 bits */
+ case 4:
+ host->caps |= MMC_CAP_4_BIT_DATA;
+ break;
+ case 1:
+ break;
+ default:
+ dev_err(host->parent,
+ "Invalid \"bus-width\" value %ud!\n", bus_width);
+ }
+
+ /* Optional property: ignore errors */
+ of_property_read_u32_array(np, "max-frequency", &host->f_max, 1);
+
+ /* Both CD and WP pins are by default active low */
+
+ /* Parse Card Detection */
+ if (of_find_property(np, "non-removable", &len)) {
+ host->caps |= MMC_CAP_NONREMOVABLE;
+ } else {
+ bool explicit_inv_cd, gpio_inv_cd = false;
+
+ explicit_inv_cd = !!of_find_property(np, "cd-inverted", &len);
+
+ if (of_find_property(np, "broken-cd", &len))
+ host->caps |= MMC_CAP_NEEDS_POLL;
+
+ gpio = of_get_named_gpio_flags(np, "cd-gpios", 0, &flags);
+ if (gpio_is_valid(gpio)) {
+ if (!(flags & OF_GPIO_ACTIVE_LOW))
+ gpio_inv_cd = true;
+
+ ret = mmc_gpio_request_cd(host, gpio);
+ if (ret < 0)
+ dev_err(host->parent,
+ "Failed to request CD GPIO #%d: %d!\n",
+ gpio, ret);
+ else
+ dev_info(host->parent, "Got CD GPIO #%d.\n",
+ gpio);
+ }
+
+ if (explicit_inv_cd ^ gpio_inv_cd)
+ host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
+ }
+
+ /* Parse Write Protection */
+ explicit_inv_wp = !!of_find_property(np, "wp-inverted", &len);
+
+ gpio = of_get_named_gpio_flags(np, "wp-gpios", 0, &flags);
+ if (gpio_is_valid(gpio)) {
+ if (!(flags & OF_GPIO_ACTIVE_LOW))
+ gpio_inv_wp = true;
+
+ ret = mmc_gpio_request_ro(host, gpio);
+ if (ret < 0)
+ dev_err(host->parent,
+ "Failed to request WP GPIO: %d!\n", ret);
+ }
+ if (explicit_inv_wp ^ gpio_inv_wp)
+ host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
+}
+
+EXPORT_SYMBOL(mmc_of_parse);
+
/**
* mmc_alloc_host - initialise the per-host structure.
* @extra: sizeof private data structure
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 61a10c1..13c0c8d 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -345,6 +345,7 @@ extern struct mmc_host *mmc_alloc_host(int extra, struct device *);
extern int mmc_add_host(struct mmc_host *);
extern void mmc_remove_host(struct mmc_host *);
extern void mmc_free_host(struct mmc_host *);
+void mmc_of_parse(struct mmc_host *host);
static inline void *mmc_priv(struct mmc_host *host)
{
--
1.7.2.5
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