Re: [PATCH v3 5/6] mmc: dw_mmc: add device tree support

Girish K S
2012-07-16T04:30:47Z

On 16 July 2012 09:45, Girish K S <girish.shivananjappa@linaro.org> wrote:
> On 12 July 2012 18:24, Thomas Abraham <thomas.abraham@linaro.org> wrote:
>> Add device tree based discovery support.
>>
>> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
>> ---
>> .../devicetree/bindings/mmc/synposis-dw-mshc.txt | 108 +++++++++++
>> drivers/mmc/host/dw_mmc-pltfm.c | 24 +++
>> drivers/mmc/host/dw_mmc.c | 201 +++++++++++++++++++-
>> drivers/mmc/host/dw_mmc.h | 9 +
>> include/linux/mmc/dw_mmc.h | 2 +
>> 5 files changed, 338 insertions(+), 6 deletions(-)
>> create mode 100644 Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
>>
>> diff --git a/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
>> new file mode 100644
>> index 0000000..3acd6c9
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
>> @@ -0,0 +1,108 @@
>> +* 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.
>> +
>> +Required Properties:
>> +
>> +* compatible: should be one of the following
>> + - snps,dw-mshc: for controllers compliant with synopsis dw-mshc.
>> +
>> +* reg: physical base address of the dw-mshc controller and size of its memory
>> + region.
>> +
>> +* interrupts: interrupt specifier for the controller. The format and value of
>> + the interrupt specifier depends on the interrupt parent for the controller.
>> +
>> +* #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: specifies the width of the data bus connected from the
>> + controller to the card slot. The value should be 1, 4 or 8. In case
>> + this property is not specified, a default value of 1 is assumed for
>> + this property.
>> +
>> + * cd-gpios: specifies the card detect gpio line. The format of the
>> + gpio specifier depends on the gpio controller.
>> +
>> + * wp-gpios: specifies the write protect gpio line. The format of the
>> + gpio specifier depends on the gpio controller.
>> +
>> + * gpios: specifies a list of gpios used for command, clock and data
>> + bus. The first gpio is the command line and the second gpio is the
>> + clock line. The rest of the gpios (depending on the bus-width
>> + property) are the data lines in no particular order. The format of
>> + the gpio specifier depends on the gpio controller.
>> +
>> +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)
>> +
>> +* card-detection-broken: The card detection functionality is not available on
>> + any of the slots.
>> +
>> +* no-write-protect: The write protect pad of the controller is not connected
>> + to the write protect pin on the slot.
>> +
>> +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;
>> + card-detection-broken;
>> + no-write-protect;
>> + fifo-depth = <0x80>;
>> + card-detect-delay = <200>;
>> +
>> + slot@0 {
>> + reg = <0>;
>> + bus-width = <8>;
>> + cd-gpios = <&gpc0 2 2 3 3>;
>> + gpios = <&gpc0 0 2 0 3>, <&gpc0 1 2 0 3>,
>> + <&gpc1 0 2 3 3>, <&gpc1 1 2 3 3>,
>> + <&gpc1 2 2 3 3>, <&gpc1 3 2 3 3>,
>> + <&gpc0 3 2 3 3>, <&gpc0 4 2 3 3>,
>> + <&gpc0 5 2 3 3>, <&gpc0 6 2 3 3>;
>> + };
>> + };
>> diff --git a/drivers/mmc/host/dw_mmc-pltfm.c b/drivers/mmc/host/dw_mmc-pltfm.c
>> index 9a63299..8d24f6d 100644
>> --- a/drivers/mmc/host/dw_mmc-pltfm.c
>> +++ b/drivers/mmc/host/dw_mmc-pltfm.c
>> @@ -19,8 +19,24 @@
>> #include <linux/mmc/host.h>
>> #include <linux/mmc/mmc.h>
>> #include <linux/mmc/dw_mmc.h>
>> +#include <linux/of.h>
>> #include "dw_mmc.h"
>>
>> +#ifdef CONFIG_OF
>> +static struct dw_mci_drv_data synopsis_drv_data = {
>> + .ctrl_type = DW_MCI_TYPE_SYNOPSIS,
>> +};
>> +
>> +static const struct of_device_id dw_mci_pltfm_match[] = {
>> + { .compatible = "snps,dw-mshc",
>> + .data = (void *)&synopsis_drv_data, },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, dw_mci_pltfm_match);
>> +#else
>> +static const struct of_device_id dw_mci_pltfm_match[];
> the #else and a statement can be completely removed if of_match_ptr is
> used while accessing the dw_mci_pltfm_match in of_match_node function.
>> +#endif
>> +
>> static int dw_mci_pltfm_probe(struct platform_device *pdev)
>> {
>> struct dw_mci *host;
>> @@ -51,6 +67,13 @@ static int dw_mci_pltfm_probe(struct platform_device *pdev)
>> if (!host->regs)
>> goto err_free;
>> platform_set_drvdata(pdev, host);
>> +
>> + if (pdev->dev.of_node) {
>> + const struct of_device_id *match;
>> + match = of_match_node(dw_mci_pltfm_match, pdev->dev.of_node);
> can be modified to of_match_node(of_match_pt(dw_mci_pltfm_match),
> pdev->dev.of_node);
> This will remove the dummy allocation of variable as mentioned above.
Sorry not allocation but declaration
> Also it will be generic in non dt case.
>> + host->drv_data = match->data;
>> + }
>> +
>> ret = dw_mci_probe(host);
>> if (ret)
>> goto err_out;
>> @@ -111,6 +134,7 @@ 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,
>> },
>> };
>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
>> index 075f89d..3bc276d 100644
>> --- a/drivers/mmc/host/dw_mmc.c
>> +++ b/drivers/mmc/host/dw_mmc.c
>> @@ -33,9 +33,13 @@
>> #include <linux/bitops.h>
>> #include <linux/regulator/consumer.h>
>> #include <linux/workqueue.h>
>> +#include <linux/of.h>
>> +#include <linux/of_gpio.h>
>>
>> #include "dw_mmc.h"
>>
>> +#define NUM_PINS(x) (x + 2)
>> +
>> /* Common flag combinations */
>> #define DW_MCI_DATA_ERROR_FLAGS (SDMMC_INT_DTO | SDMMC_INT_DCRC | \
>> SDMMC_INT_HTO | SDMMC_INT_SBE | \
>> @@ -86,6 +90,8 @@ struct idmac_desc {
>> struct dw_mci_slot {
>> struct mmc_host *mmc;
>> struct dw_mci *host;
>> + int wp_gpio;
>> + int cd_gpio;
>>
>> u32 ctype;
>>
>> @@ -1762,10 +1768,106 @@ static void dw_mci_work_routine_card(struct work_struct *work)
>> }
>> }
>>
>> +#ifdef CONFIG_OF
>> +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;
>> +}
>> +
>> +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;
>> +}
>> +
>> +static int dw_mci_of_setup_bus(struct dw_mci *host, u8 slot, u32 bus_wd)
>> +{
>> + struct device_node *np = dw_mci_of_find_slot_node(host->dev, slot);
>> + int idx, gpio, ret;
>> +
>> + if (!np)
>> + return -EINVAL;
>> +
>> + for (idx = 0; idx < NUM_PINS(bus_wd); idx++) {
>> + gpio = of_get_gpio(np, idx);
>> + if (!gpio_is_valid(gpio)) {
>> + dev_err(host->dev, "invalid gpio: %d\n", gpio);
>> + return -EINVAL;
>> + }
>> +
>> + ret = devm_gpio_request(host->dev, gpio, "dw-mci-bus");
>> + if (ret) {
>> + dev_err(host->dev, "gpio [%d] request failed\n", gpio);
>> + return -EBUSY;
>> + }
>> + }
>> +
>> + host->slot[slot]->wp_gpio = -1;
>> + gpio = of_get_named_gpio(np, "wp-gpios", 0);
>> + if (!gpio_is_valid(gpio)) {
>> + dev_info(host->dev, "wp gpio not available");
>> + } else {
>> + ret = devm_gpio_request(host->dev, gpio, "dw-mci-wp");
>> + if (ret)
>> + dev_info(host->dev, "gpio [%d] request failed\n",
>> + gpio);
>> + else
>> + host->slot[slot]->wp_gpio = gpio;
>> + }
>> +
>> + host->slot[slot]->cd_gpio = -1;
>> + gpio = of_get_named_gpio(np, "cd-gpios", 0);
>> + if (!gpio_is_valid(gpio)) {
>> + dev_info(host->dev, "cd gpio not available");
>> + } else {
>> + ret = devm_gpio_request(host->dev, gpio, "dw-mci-cd");
>> + if (ret)
>> + dev_err(host->dev, "gpio [%d] request failed\n", gpio);
>> + else
>> + host->slot[slot]->cd_gpio = gpio;
>> + }
>> +
>> + return 0;
>> +}
>> +#else /* CONFIG_OF */
>> +static u32 dw_mci_of_get_bus_wd(struct device *dev, u8 slot)
>> +{
>> + return 1;
>> +}
>> +
>> +static int dw_mci_of_setup_bus(struct dw_mci *host, u8 slot, u32 bus_wd)
>> +{
>> + return -EINVAL;
>> +}
>> +#endif /* CONFIG_OF */
>> +
>> static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id)
>> {
>> struct mmc_host *mmc;
>> struct dw_mci_slot *slot;
>> + int ctrl_id, ret;
>>
>> mmc = mmc_alloc_host(sizeof(struct dw_mci_slot), host->dev);
>> if (!mmc)
>> @@ -1775,6 +1877,7 @@ static int __init 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);
>> @@ -1795,12 +1898,33 @@ static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id)
>> if (host->pdata->caps)
>> mmc->caps = host->pdata->caps;
>>
>> + if (host->dev->of_node) {
>> + ctrl_id = of_alias_get_id(host->dev->of_node, "mshc");
>> + if (ctrl_id < 0)
>> + ctrl_id = 0;
>> + }
>> + if (host->drv_data->caps)
>> + mmc->caps |= host->drv_data->caps[ctrl_id];
>> +
>> if (host->pdata->caps2)
>> mmc->caps2 = host->pdata->caps2;
>>
>> - if (host->pdata->get_bus_wd)
>> + if (host->pdata->get_bus_wd) {
>> if (host->pdata->get_bus_wd(slot->id) >= 4)
>> mmc->caps |= MMC_CAP_4_BIT_DATA;
>> + } else if (host->dev->of_node) {
>> + unsigned int bus_width;
>> + bus_width = dw_mci_of_get_bus_wd(host->dev, slot->id);
>> + switch (bus_width) {
>> + case 8:
>> + mmc->caps |= MMC_CAP_8_BIT_DATA;
>> + case 4:
>> + mmc->caps |= MMC_CAP_4_BIT_DATA;
>> + }
>> + ret = dw_mci_of_setup_bus(host, slot->id, bus_width);
>> + if (ret)
>> + goto err_setup_bus;
>> + }
>>
>> if (host->pdata->quirks & DW_MCI_QUIRK_HIGHSPEED)
>> mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED;
>> @@ -1845,7 +1969,6 @@ static int __init 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)
>> @@ -1862,6 +1985,10 @@ static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id)
>> queue_work(host->card_workqueue, &host->card_work);
>>
>> return 0;
>> +
>> +err_setup_bus:
>> + mmc_free_host(mmc);
>> + return -EINVAL;
>> }
>>
>> static void dw_mci_cleanup_slot(struct dw_mci_slot *slot, unsigned int id)
>> @@ -1937,16 +2064,78 @@ 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_quriks[] = {
>> + {
>> + .quirk = "supports-highspeed",
>> + .id = DW_MCI_QUIRK_HIGHSPEED,
>> + }, {
>> + .quirk = "card-detection-broken",
>> + .id = DW_MCI_QUIRK_BROKEN_CARD_DETECTION,
>> + }, {
>> + .quirk = "no-write-protect",
>> + .id = DW_MCI_QUIRK_NO_WRITE_PROTECT,
>> + }
>> +};
>> +
>> +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, cnt;
>> +
>> + 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 */
>> + cnt = sizeof(of_quriks) / sizeof(struct dw_mci_of_quirks);
>> + for (idx = 0; idx < cnt; idx++)
>> + if (of_get_property(np, of_quriks[idx].quirk, NULL))
>> + pdata->quirks |= of_quriks[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) {
>> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
>> index 15c27e1..1ecaa02 100644
>> --- a/drivers/mmc/host/dw_mmc.h
>> +++ b/drivers/mmc/host/dw_mmc.h
>> @@ -182,4 +182,13 @@ extern int dw_mci_suspend(struct dw_mci *host);
>> extern int dw_mci_resume(struct dw_mci *host);
>> #endif
>>
>> +/* Variations in the dw_mci controller */
>> +#define DW_MCI_TYPE_SYNOPSIS 0
>> +
>> +/* dw_mci platform driver data */
>> +struct dw_mci_drv_data {
>> + unsigned long ctrl_type;
>> + unsigned long *caps;
>> +};
>> +
>> #endif /* _DW_MMC_H_ */
>> diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
>> index b72e4aa..ae45e4f 100644
>> --- a/include/linux/mmc/dw_mmc.h
>> +++ b/include/linux/mmc/dw_mmc.h
>> @@ -78,6 +78,7 @@ struct mmc_data;
>> * @data_offset: Set the offset of DATA register according to VERID.
>> * @dev: Device associated with the MMC controller.
>> * @pdata: Platform data associated with the MMC controller.
>> + * @drv_data: Driver specific data for identified variant of the controller
>> * @biu_clk: Pointer to bus interface unit clock instance.
>> * @ciu_clk: Pointer to card interface unit clock instance.
>> * @slot: Slots sharing this MMC controller.
>> @@ -160,6 +161,7 @@ struct dw_mci {
>> u16 data_offset;
>> struct device *dev;
>> struct dw_mci_board *pdata;
>> + struct dw_mci_drv_data *drv_data;
>> struct clk *biu_clk;
>> struct clk *ciu_clk;
>> struct dw_mci_slot *slot[MAX_MCI_SLOTS];
>> --
>> 1.6.6.rc2
>>
>> --
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