Commit c91eab4b authored by Thomas Abraham's avatar Thomas Abraham Committed by Chris Ball

mmc: dw_mmc: add device tree support

Add device tree based discovery support.
Signed-off-by: default avatarThomas Abraham <thomas.abraham@linaro.org>
Acked-by: default avatarWill Newton <will.newton@imgtec.com>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent b4967aa5
* Synopsis Designware Mobile Storage Host Controller
The Synopsis designware mobile storage host controller is used to interface
a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
differences between the core mmc properties described by mmc.txt and the
properties used by the Synopsis Designware Mobile Storage Host Controller.
Required Properties:
* compatible: should be
- snps,dw-mshc: for controllers compliant with synopsis dw-mshc.
* #address-cells: should be 1.
* #size-cells: should be 0.
# Slots: The slot specific information are contained within child-nodes with
each child-node representing a supported slot. There should be atleast one
child node representing a card slot. The name of the child node representing
the slot is recommended to be slot@n where n is the unique number of the slot
connnected to the controller. The following are optional properties which
can be included in the slot child node.
* reg: specifies the physical slot number. The valid values of this
property is 0 to (num-slots -1), where num-slots is the value
specified by the num-slots property.
* bus-width: as documented in mmc core bindings.
* wp-gpios: specifies the write protect gpio line. The format of the
gpio specifier depends on the gpio controller. If the write-protect
line is not available, this property is optional.
Optional properties:
* num-slots: specifies the number of slots supported by the controller.
The number of physical slots actually used could be equal or less than the
value specified by num-slots. If this property is not specified, the value
of num-slot property is assumed to be 1.
* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
specified, the default value of the fifo size is determined from the
controller registers.
* card-detect-delay: Delay in milli-seconds before detecting card after card
insert event. The default value is 0.
* supports-highspeed: Enables support for high speed cards (upto 50MHz)
* broken-cd: as documented in mmc core bindings.
Aliases:
- All the MSHC controller nodes should be represented in the aliases node using
the following format 'mshc{n}' where n is a unique number for the alias.
Example:
The MSHC controller node can be split into two portions, SoC specific and
board specific portions as listed below.
dwmmc0@12200000 {
compatible = "snps,dw-mshc";
reg = <0x12200000 0x1000>;
interrupts = <0 75 0>;
#address-cells = <1>;
#size-cells = <0>;
};
dwmmc0@12200000 {
num-slots = <1>;
supports-highspeed;
broken-cd;
fifo-depth = <0x80>;
card-detect-delay = <200>;
slot@0 {
reg = <0>;
bus-width = <8>;
};
};
......@@ -19,6 +19,8 @@
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/dw_mmc.h>
#include <linux/of.h>
#include "dw_mmc.h"
static int __devinit dw_mci_pltfm_probe(struct platform_device *pdev)
......@@ -94,10 +96,17 @@ static int dw_mci_pltfm_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(dw_mci_pltfm_pmops, dw_mci_pltfm_suspend, dw_mci_pltfm_resume);
static const struct of_device_id dw_mci_pltfm_match[] = {
{ .compatible = "snps,dw-mshc", },
{},
};
MODULE_DEVICE_TABLE(of, dw_mci_pltfm_match);
static struct platform_driver dw_mci_pltfm_driver = {
.remove = __exit_p(dw_mci_pltfm_remove),
.driver = {
.name = "dw_mmc",
.of_match_table = of_match_ptr(dw_mci_pltfm_match),
.pm = &dw_mci_pltfm_pmops,
},
};
......
......@@ -33,6 +33,7 @@
#include <linux/bitops.h>
#include <linux/regulator/consumer.h>
#include <linux/workqueue.h>
#include <linux/of.h>
#include "dw_mmc.h"
......@@ -1769,10 +1770,57 @@ static void dw_mci_work_routine_card(struct work_struct *work)
}
}
#ifdef CONFIG_OF
/* given a slot id, find out the device node representing that slot */
static struct device_node *dw_mci_of_find_slot_node(struct device *dev, u8 slot)
{
struct device_node *np;
const __be32 *addr;
int len;
if (!dev || !dev->of_node)
return NULL;
for_each_child_of_node(dev->of_node, np) {
addr = of_get_property(np, "reg", &len);
if (!addr || (len < sizeof(int)))
continue;
if (be32_to_cpup(addr) == slot)
return np;
}
return NULL;
}
/* find out bus-width for a given slot */
static u32 dw_mci_of_get_bus_wd(struct device *dev, u8 slot)
{
struct device_node *np = dw_mci_of_find_slot_node(dev, slot);
u32 bus_wd = 1;
if (!np)
return 1;
if (of_property_read_u32(np, "bus-width", &bus_wd))
dev_err(dev, "bus-width property not found, assuming width"
" as 1\n");
return bus_wd;
}
#else /* CONFIG_OF */
static u32 dw_mci_of_get_bus_wd(struct device *dev, u8 slot)
{
return 1;
}
static struct device_node *dw_mci_of_find_slot_node(struct device *dev, u8 slot)
{
return NULL;
}
#endif /* CONFIG_OF */
static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
{
struct mmc_host *mmc;
struct dw_mci_slot *slot;
u8 bus_width;
mmc = mmc_alloc_host(sizeof(struct dw_mci_slot), host->dev);
if (!mmc)
......@@ -1782,6 +1830,7 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
slot->id = id;
slot->mmc = mmc;
slot->host = host;
host->slot[id] = slot;
mmc->ops = &dw_mci_ops;
mmc->f_min = DIV_ROUND_UP(host->bus_hz, 510);
......@@ -1806,8 +1855,18 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
mmc->caps2 = host->pdata->caps2;
if (host->pdata->get_bus_wd)
if (host->pdata->get_bus_wd(slot->id) >= 4)
mmc->caps |= MMC_CAP_4_BIT_DATA;
bus_width = host->pdata->get_bus_wd(slot->id);
else if (host->dev->of_node)
bus_width = dw_mci_of_get_bus_wd(host->dev, slot->id);
else
bus_width = 1;
switch (bus_width) {
case 8:
mmc->caps |= MMC_CAP_8_BIT_DATA;
case 4:
mmc->caps |= MMC_CAP_4_BIT_DATA;
}
if (host->pdata->quirks & DW_MCI_QUIRK_HIGHSPEED)
mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED;
......@@ -1852,7 +1911,6 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
else
clear_bit(DW_MMC_CARD_PRESENT, &slot->flags);
host->slot[id] = slot;
mmc_add_host(mmc);
#if defined(CONFIG_DEBUG_FS)
......@@ -1944,16 +2002,74 @@ static bool mci_wait_reset(struct device *dev, struct dw_mci *host)
return false;
}
#ifdef CONFIG_OF
static struct dw_mci_of_quirks {
char *quirk;
int id;
} of_quirks[] = {
{
.quirk = "supports-highspeed",
.id = DW_MCI_QUIRK_HIGHSPEED,
}, {
.quirk = "broken-cd",
.id = DW_MCI_QUIRK_BROKEN_CARD_DETECTION,
},
};
static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
{
struct dw_mci_board *pdata;
struct device *dev = host->dev;
struct device_node *np = dev->of_node;
int idx;
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata) {
dev_err(dev, "could not allocate memory for pdata\n");
return ERR_PTR(-ENOMEM);
}
/* find out number of slots supported */
if (of_property_read_u32(dev->of_node, "num-slots",
&pdata->num_slots)) {
dev_info(dev, "num-slots property not found, "
"assuming 1 slot is available\n");
pdata->num_slots = 1;
}
/* get quirks */
for (idx = 0; idx < ARRAY_SIZE(of_quirks); idx++)
if (of_get_property(np, of_quirks[idx].quirk, NULL))
pdata->quirks |= of_quirks[idx].id;
if (of_property_read_u32(np, "fifo-depth", &pdata->fifo_depth))
dev_info(dev, "fifo-depth property not found, using "
"value of FIFOTH register as default\n");
of_property_read_u32(np, "card-detect-delay", &pdata->detect_delay_ms);
return pdata;
}
#else /* CONFIG_OF */
static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
{
return ERR_PTR(-EINVAL);
}
#endif /* CONFIG_OF */
int dw_mci_probe(struct dw_mci *host)
{
int width, i, ret = 0;
u32 fifo_size;
int init_slots = 0;
if (!host->pdata || !host->pdata->init) {
dev_err(host->dev,
"Platform data must supply init function\n");
return -ENODEV;
if (!host->pdata) {
host->pdata = dw_mci_parse_dt(host);
if (IS_ERR(host->pdata)) {
dev_err(host->dev, "platform data not available\n");
return -EINVAL;
}
}
if (!host->pdata->select_slot && host->pdata->num_slots > 1) {
......
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