[PATCH v3 1/3] mmc: atmel-mci: add device tree support
Nicolas Ferre
nicolas.ferre at atmel.com
Tue May 22 08:55:09 EDT 2012
On 05/22/2012 12:09 PM, ludovic.desroches at atmel.com :
> From: Ludovic Desroches <ludovic.desroches at atmel.com>
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches at atmel.com>
Looks neat!
Acked-by: Nicolas Ferre <nicolas.ferre at atmel.com>
> ---
> .../devicetree/bindings/mmc/atmel-hsmci.txt | 67 +++++++++++++++
> drivers/mmc/host/atmel-mci.c | 89 +++++++++++++++++++-
> 2 files changed, 154 insertions(+), 2 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
>
> diff --git a/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt b/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
> new file mode 100644
> index 0000000..81c20cc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
> @@ -0,0 +1,67 @@
> +* Atmel High Speed MultiMedia Card Interface
> +
> +This controller on atmel products provides an interface for MMC, SD and SDIO
> +types of memory cards.
> +
> +1) MCI node
> +
> +Required properties:
> +- compatible: no blank "atmel,hsmci"
> +- reg: should contain HSMCI registers location and length
> +- interrupts: should contain HSMCI interrupt number
> +- #address-cells: should be one. The cell is the slot id.
> +- #size-cells: should be zero.
> +- at least one slot node
> +
> +The node contains child nodes for each slot that the platform uses
> +
> +Example MCI node:
> +
> +mmc0: mmc at f0008000 {
> + compatible = "atmel,hsmci";
> + reg = <0xf0008000 0x600>;
> + interrupts = <12 4>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + [ child node definitions...]
> +};
> +
> +2) slot nodes
> +
> +Required properties:
> +- reg: should contain the slot id.
> +- bus-width: number of data lines connected to the controller
> +
> +Optional properties:
> +- cd-gpios: specify GPIOs for card detection
> +- cd-inverted: invert the value of external card detect gpio line
> +- wp-gpios: specify GPIOs for write protection
> +
> +Example slot node:
> +
> +slot at 0 {
> + reg = <0>;
> + bus-width = <4>;
> + cd-gpios = <&pioD 15 0>
> + cd-inverted;
> +};
> +
> +Example full MCI node:
> +mmc0: mmc at f0008000 {
> + compatible = "atmel,hsmci";
> + reg = <0xf0008000 0x600>;
> + interrupts = <12 4>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + slot at 0 {
> + reg = <0>;
> + bus-width = <4>;
> + cd-gpios = <&pioD 15 0>
> + cd-inverted;
> + };
> + slot at 1 {
> + reg = <1>;
> + bus-width = <4>;
> + };
> +};
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 556d384..43f98fc 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -19,6 +19,9 @@
> #include <linux/interrupt.h>
> #include <linux/ioport.h>
> #include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
> #include <linux/platform_device.h>
> #include <linux/scatterlist.h>
> #include <linux/seq_file.h>
> @@ -493,6 +496,74 @@ err:
> dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
> }
>
> +#if defined(CONFIG_OF)
> +static const struct of_device_id atmci_dt_ids[] = {
> + { .compatible = "atmel,hsmci" },
> + { /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, atmci_dt_ids);
> +
> +static struct mci_platform_data __devinit*
> +atmci_of_init(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct device_node *cnp;
> + struct mci_platform_data *pdata;
> + unsigned int slot_id;
> + const __be32 *reg;
> +
> + if (!np) {
> + dev_err(&pdev->dev, "device node not found\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata) {
> + dev_err(&pdev->dev, "could not allocate memory for pdata\n");
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + for_each_child_of_node(np, cnp) {
> + reg = of_get_property(cnp, "reg", NULL);
> + if (!reg) {
> + dev_warn(&pdev->dev, "reg property is missing for %s\n",
> + cnp->full_name);
> + continue;
> + }
> +
> + slot_id = be32_to_cpu(reg[0]);
> +
> + if (slot_id > (ATMCI_MAX_NR_SLOTS-1)) {
> + dev_warn(&pdev->dev, "can't have more than %d slots\n",
> + ATMCI_MAX_NR_SLOTS);
> + break;
> + }
> +
> + if (of_property_read_u32(cnp, "bus-width",
> + &pdata->slot[slot_id].bus_width))
> + pdata->slot[slot_id].bus_width = 1;
> +
> + pdata->slot[slot_id].detect_pin =
> + of_get_named_gpio(cnp, "cd-gpios", 0);
> +
> + if (of_find_property(cnp, "cd-inverted", NULL))
> + pdata->slot[slot_id].detect_is_active_high = true;
> +
> + pdata->slot[slot_id].wp_pin =
> + of_get_named_gpio(cnp, "wp-gpios", 0);
> + }
> +
> + return pdata;
> +}
> +#else /* CONFIG_OF */
> +static inline struct mci_platform_data*
> +atmci_of_init(struct platform_device *dev)
> +{
> + return ERR_PTR(-EINVAL);
> +}
> +#endif
> +
> static inline unsigned int atmci_get_version(struct atmel_mci *host)
> {
> return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
> @@ -2038,6 +2109,13 @@ static int __init atmci_init_slot(struct atmel_mci *host,
> slot->sdc_reg = sdc_reg;
> slot->sdio_irq = sdio_irq;
>
> + dev_dbg(&mmc->class_dev,
> + "slot[%u]: bus_width=%u, detect_pin=%d, "
> + "detect_is_active_high=%s, wp_pin=%d\n",
> + id, slot_data->bus_width, slot_data->detect_pin,
> + slot_data->detect_is_active_high ? "true" : "false",
> + slot_data->wp_pin);
> +
> mmc->ops = &atmci_ops;
> mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
> mmc->f_max = host->bus_hz / 2;
> @@ -2258,8 +2336,14 @@ static int __init atmci_probe(struct platform_device *pdev)
> if (!regs)
> return -ENXIO;
> pdata = pdev->dev.platform_data;
> - if (!pdata)
> - return -ENXIO;
> + if (!pdata) {
> + pdata = atmci_of_init(pdev);
> + if (IS_ERR(pdata)) {
> + dev_err(&pdev->dev, "platform data not available\n");
> + return -EINVAL;
> + }
> + }
> +
> irq = platform_get_irq(pdev, 0);
> if (irq < 0)
> return irq;
> @@ -2477,6 +2561,7 @@ static struct platform_driver atmci_driver = {
> .driver = {
> .name = "atmel_mci",
> .pm = ATMCI_PM_OPS,
> + .of_match_table = of_match_ptr(atmci_dt_ids),
> },
> };
>
--
Nicolas Ferre
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