mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
mmc: provide a standard MMC device-tree binding parser centrally
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(). Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
parent
6da15e96fb
commit
6c56e7a0ff
2 changed files with 111 additions and 0 deletions
|
@ -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 +297,113 @@ static inline void mmc_host_clk_sysfs_init(struct mmc_host *host)
|
|||
|
||||
#endif
|
||||
|
||||
/**
|
||||
* mmc_of_parse() - parse host's device-tree node
|
||||
* @host: host whose node should be parsed.
|
||||
*
|
||||
* To keep the rest of the MMC subsystem unaware of whether DT has been
|
||||
* used to to instantiate and configure this host instance or not, we
|
||||
* parse the properties and set respective generic mmc-host flags and
|
||||
* parameters.
|
||||
*/
|
||||
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;
|
||||
|
||||
/* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
|
||||
if (of_property_read_u32(np, "bus-width", &bus_width) < 0) {
|
||||
dev_dbg(host->parent,
|
||||
"\"bus-width\" property is missing, assuming 1 bit.\n");
|
||||
bus_width = 1;
|
||||
}
|
||||
|
||||
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);
|
||||
}
|
||||
|
||||
/* f_max is obtained from the optional "max-frequency" property */
|
||||
of_property_read_u32(np, "max-frequency", &host->f_max);
|
||||
|
||||
/*
|
||||
* Configure CD and WP pins. They are both by default active low to
|
||||
* match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
|
||||
* mmc-gpio helpers are used to attach, configure and use them. If
|
||||
* polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
|
||||
* and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
|
||||
* "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
|
||||
* is set. If the "non-removable" property is found, the
|
||||
* MMC_CAP_NONREMOVABLE capability is set and no card-detection
|
||||
* configuration is performed.
|
||||
*/
|
||||
|
||||
/* 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_property_read_bool(np, "cd-inverted");
|
||||
|
||||
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_property_read_bool(np, "wp-inverted");
|
||||
|
||||
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
|
||||
|
|
|
@ -368,6 +368,7 @@ 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)
|
||||
{
|
||||
|
|
Loading…
Reference in a new issue