[PATCH v2 5/9] gpio: pxa: parse gpio from DTS file
Grant Likely
grant.likely at secretlab.ca
Tue May 8 15:40:27 EDT 2012
On Fri, 4 May 2012 20:30:22 +0800, Haojian Zhuang <haojian.zhuang at gmail.com> wrote:
> Parse GPIO numbers from DTS file. Allocate interrupt according to
> GPIO numbers.
>
> Signed-off-by: Haojian Zhuang <haojian.zhuang at gmail.com>
> ---
> drivers/gpio/gpio-pxa.c | 116 +++++++++++++++++++++++++++++++++++++++-------
> 1 files changed, 98 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
> index fc3ace3..58a6a63 100644
> --- a/drivers/gpio/gpio-pxa.c
> +++ b/drivers/gpio/gpio-pxa.c
> @@ -11,13 +11,17 @@
> * it under the terms of the GNU General Public License version 2 as
> * published by the Free Software Foundation.
> */
> +#include <linux/module.h>
> #include <linux/clk.h>
> #include <linux/err.h>
> #include <linux/gpio.h>
> #include <linux/gpio-pxa.h>
> #include <linux/init.h>
> #include <linux/irq.h>
> +#include <linux/irqdomain.h>
> #include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> #include <linux/platform_device.h>
> #include <linux/syscore_ops.h>
> #include <linux/slab.h>
> @@ -56,6 +60,10 @@
>
> int pxa_last_gpio;
>
> +#ifdef CONFIG_OF
> +static struct irq_domain *domain;
> +#endif
> +
> struct pxa_gpio_chip {
> struct gpio_chip chip;
> void __iomem *regbase;
> @@ -81,7 +89,6 @@ enum {
> PXA3XX_GPIO,
> PXA93X_GPIO,
> MMP_GPIO = 0x10,
> - MMP2_GPIO,
> };
>
> static DEFINE_SPINLOCK(gpio_lock);
> @@ -475,22 +482,92 @@ static int pxa_gpio_nums(void)
> gpio_type = MMP_GPIO;
> } else if (cpu_is_mmp2()) {
> count = 191;
> - gpio_type = MMP2_GPIO;
> + gpio_type = MMP_GPIO;
> }
> #endif /* CONFIG_ARCH_MMP */
> return count;
> }
>
> +static struct of_device_id pxa_gpio_dt_ids[] = {
> + { .compatible = "mrvl,pxa-gpio" },
> + { .compatible = "mrvl,mmp-gpio", .data = (void *)MMP_GPIO },
> + {}
> +};
> +
> +static int pxa_irq_domain_map(struct irq_domain *d, unsigned int irq,
> + irq_hw_number_t hw)
> +{
> + irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
> + handle_edge_irq);
> + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> + return 0;
> +}
> +
> +const struct irq_domain_ops pxa_irq_domain_ops = {
> + .map = pxa_irq_domain_map,
> +};
> +
> +#ifdef CONFIG_OF
> +static int __devinit pxa_gpio_probe_dt(struct platform_device *pdev)
> +{
> + int ret, nr_banks, nr_gpios, irq_base;
> + struct device_node *prev, *next, *np = pdev->dev.of_node;
> + const struct of_device_id *of_id =
> + of_match_device(pxa_gpio_dt_ids, &pdev->dev);
> +
> + if (!of_id) {
> + dev_err(&pdev->dev, "Failed to find gpio controller\n");
> + return -EFAULT;
> + }
> + gpio_type = (int)of_id->data;
> +
> + next = of_get_next_child(np, NULL);
> + prev = next;
> + if (!next) {
> + dev_err(&pdev->dev, "Failed to find child gpio node\n");
> + ret = -EINVAL;
> + goto err;
> + }
> + for (nr_banks = 1; ; nr_banks++) {
> + next = of_get_next_child(np, prev);
> + if (!next)
> + break;
> + prev = next;
> + }
> + of_node_put(prev);
> + nr_gpios = nr_banks << 5;
> + pxa_last_gpio = nr_gpios - 1;
> +
> + irq_base = irq_alloc_descs(-1, 0, nr_gpios, 0);
> + if (irq_base < 0) {
> + dev_err(&pdev->dev, "Failed to allocate IRQ numbers\n");
> + goto err;
> + }
> + domain = irq_domain_add_legacy(np, nr_gpios, irq_base, 0,
> + &pxa_irq_domain_ops, NULL);
> + return 0;
Instead of putting the irq_domain_add_legacy() call into the DT-only
path, the entire driver should be converted over to use an irq_domain.
That will keep the driver simpler overall.
Also, as part of the conversion to irq_domain the irq handling
functions and the *_gpio_to_irq functions need to be refactored to use
irq_find_mapping() instead of a hard coded offset. Also, the hwirq
number (which should always equal the gpio number) is now available in
irq_data via irq->hwirq.
So, for example, pxa_gpio_irq_type does:
int gpio = pxa_irq_to_gpio(d->irq);
but now it can simply be:
int gpio = d->irq;
> +err:
> + iounmap(gpio_reg_base);
> + return ret;
> +}
> +#else
> +#define pxa_gpio_probe_dt(pdev) (-1)
> +#endif
> +
> static int __devinit pxa_gpio_probe(struct platform_device *pdev)
> {
> struct pxa_gpio_chip *c;
> struct resource *res;
> struct clk *clk;
> struct pxa_gpio_platform_data *info;
> - int gpio, irq, ret;
> + int gpio, irq, ret, use_of = 0;
> int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;
>
> - pxa_last_gpio = pxa_gpio_nums();
> + ret = pxa_gpio_probe_dt(pdev);
> + if (ret < 0)
> + pxa_last_gpio = pxa_gpio_nums();
> + else
> + use_of = 1;
> if (!pxa_last_gpio)
> return -EINVAL;
>
> @@ -545,25 +622,27 @@ static int __devinit pxa_gpio_probe(struct platform_device *pdev)
> writel_relaxed(~0, c->regbase + ED_MASK_OFFSET);
> }
>
> + if (!use_of) {
> #ifdef CONFIG_ARCH_PXA
> - irq = gpio_to_irq(0);
> - irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
> - handle_edge_irq);
> - set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> - irq_set_chained_handler(IRQ_GPIO0, pxa_gpio_demux_handler);
> -
> - irq = gpio_to_irq(1);
> - irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
> - handle_edge_irq);
> - set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> - irq_set_chained_handler(IRQ_GPIO1, pxa_gpio_demux_handler);
> -#endif
> + irq = gpio_to_irq(0);
> + irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
> + handle_edge_irq);
> + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> + irq_set_chained_handler(IRQ_GPIO0, pxa_gpio_demux_handler);
>
> - for (irq = gpio_to_irq(gpio_offset);
> - irq <= gpio_to_irq(pxa_last_gpio); irq++) {
> + irq = gpio_to_irq(1);
> irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
> handle_edge_irq);
> set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> + irq_set_chained_handler(IRQ_GPIO1, pxa_gpio_demux_handler);
> +#endif
See? With this patch the mapping mechanism is duplicated for DT and
non-DT. If the legacy mapping was registered here, then there the
duplicate code path goes away.
> +
> + for (irq = gpio_to_irq(gpio_offset);
> + irq <= gpio_to_irq(pxa_last_gpio); irq++) {
> + irq_set_chip_and_handler(irq, &pxa_muxed_gpio_chip,
> + handle_edge_irq);
> + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> + }
> }
>
> irq_set_chained_handler(irq_mux, pxa_gpio_demux_handler);
> @@ -574,6 +653,7 @@ static struct platform_driver pxa_gpio_driver = {
> .probe = pxa_gpio_probe,
> .driver = {
> .name = "pxa-gpio",
> + .of_match_table = pxa_gpio_dt_ids,
> },
> };
>
> --
> 1.7.5.4
>
--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
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