On Fri, 16 Jan 2015, Robert Jarzmik wrote:
> Lubbock () board is the IO motherboard of the Intel PXA25x Development
> Platform, which supports the Lubbock pxa25x soc board.
>
> Historically, this support was in arch/arm/mach-pxa/lubbock.c. When
> gpio-pxa was moved to drivers/pxa, it became a driver, and its
> initialization and probing happened at postcore initcall. The lubbock
> code used to install the chained lubbock interrupt handler at init_irq()
> time.
>
> The consequence of the gpio-pxa change is that the installed chained irq
> handler lubbock_irq_handler() was overwritten in pxa_gpio_probe(_dt)(),
> removing :
> - the handler
> - the falling edge detection setting of GPIO0, which revealed the
> interrupt request from the lubbock IO board.
>
> As a fix, move the gpio0 chained handler setup to a place where we have
> the guarantee that pxa_gpio_probe() was called before, so that lubbock
> handler becomes the true IRQ chained handler of GPIO0, demuxing the
> lubbock IO board interrupts.
How is this guaranteed?
> This patch moves all that handling to a mfd driver. It's only purpose
> for the time being is the interrupt handling, but in the future it
> should encompass all the motherboard CPLDs handling :
> - leds
> - switches
> - hexleds
>
> Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
> ---
> Since v1: change the name from cottula to lubbock_io
> Dmitry pointed out the Cottula was the pxa25x family name,
> lubbock was the pxa25x development board name. Therefore the
> name was changed to lubbock_io (lubbock IO board)
> change the resources to bi-irq ioresource
> Discussion between Arnd and Robert to change the gpio
> request by a irq request.
> Since v2: take into account Mark's review
> Use irq flags from resources (DT case and pdata case).
> Change of name from lubbock_io to lubbock-io
> ---
> drivers/mfd/Kconfig | 10 +++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/lubbock.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 207 insertions(+)
> create mode 100644 drivers/mfd/lubbock.c
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 2e6b731..4d8939f 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -91,6 +91,16 @@ config MFD_AXP20X
> components like regulators or the PEK (Power Enable Key) under the
> corresponding menus.
>
> +config MFD_LUBBOCK
> + bool "Lubbock Motherboard"
> + def_bool ARCH_LUBBOCK
> + select MFD_CORE
> + help
> + This driver supports the Lubbock multifunction chip found on the
> + pxa25x development platform system (named Lubbock). This IO board
> + supports the interrupts handling, ethernet controller, flash chips,
> + etc ...
> +
> config MFD_CROS_EC
> tristate "ChromeOS Embedded Controller"
> select MFD_CORE
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 53467e2..aff1f4f 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -9,6 +9,7 @@ obj-$(CONFIG_MFD_88PM805) += 88pm805.o 88pm80x.o
> obj-$(CONFIG_MFD_SM501) += sm501.o
> obj-$(CONFIG_MFD_ASIC3) += asic3.o tmio_core.o
> obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o
> +obj-$(CONFIG_MFD_LUBBOCK) += lubbock.o
> obj-$(CONFIG_MFD_CROS_EC) += cros_ec.o
> obj-$(CONFIG_MFD_CROS_EC_I2C) += cros_ec_i2c.o
> obj-$(CONFIG_MFD_CROS_EC_SPI) += cros_ec_spi.o
> diff --git a/drivers/mfd/lubbock.c b/drivers/mfd/lubbock.c
> new file mode 100644
> index 0000000..6025135
> --- /dev/null
> +++ b/drivers/mfd/lubbock.c
> @@ -0,0 +1,196 @@
> +/*
> + * Intel Cotulla MFD - lubbock motherboard
> + *
> + * Copyright (C) 2014 Robert Jarzmik
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * Lubbock motherboard driver, supporting lubbock (aka. pxa25x) soc board.
Please use uppercase characters i.e. Lubbock, PXA25X, SoC, etc.
> + *
Superfluous '\n'.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
Can this be built as a module?
If so, why isn't it a tristate?
> +#include <linux/of_platform.h>
> +
> +#define COT_IRQ_MASK_EN 0xc0
> +#define COT_IRQ_SET_CLR 0xd0
> +
> +#define LUBBOCK_NB_IRQ 8
> +
> +struct lubbock {
> + void __iomem *base;
Random spacing.
> + int irq;
> + unsigned int irq_mask;
> + struct gpio_desc *gpio0;
> + struct irq_domain *irqdomain;
> +};
> +
> +static irqreturn_t lubbock_irq_handler(int in_irq, void *d)
> +{
> + struct lubbock *cot = d;
> + unsigned long pending;
> + unsigned int bit;
> +
> + pending = readl(cot->base + COT_IRQ_SET_CLR) & cot->irq_mask;
> + for_each_set_bit(bit, &pending, LUBBOCK_NB_IRQ)
> + generic_handle_irq(irq_find_mapping(cot->irqdomain, bit));
I'd like to see a '\n' here.
> + return IRQ_HANDLED;
> +}
> +
> +static void lubbock_irq_mask_ack(struct irq_data *d)
> +{
> + struct lubbock *cot = irq_data_get_irq_chip_data(d);
> + unsigned int lubbock_irq = irqd_to_hwirq(d);
> + unsigned int set, bit = BIT(lubbock_irq);
> +
> + cot->irq_mask &= ~bit;
> + writel(cot->irq_mask, cot->base + COT_IRQ_MASK_EN);
> + set = readl(cot->base + COT_IRQ_SET_CLR);
> + writel(set & ~bit, cot->base + COT_IRQ_SET_CLR);
> +}
> +
> +static void lubbock_irq_unmask(struct irq_data *d)
> +{
> + struct lubbock *cot = irq_data_get_irq_chip_data(d);
> + unsigned int lubbock_irq = irqd_to_hwirq(d);
> + unsigned int bit = BIT(lubbock_irq);
> +
> + cot->irq_mask |= bit;
> + writel(cot->irq_mask, cot->base + COT_IRQ_MASK_EN);
> +}
> +
> +static struct irq_chip lubbock_irq_chip = {
> + .name = "lubbock",
> + .irq_mask_ack = lubbock_irq_mask_ack,
> + .irq_unmask = lubbock_irq_unmask,
> + .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE,
> +};
> +
> +static int lubbock_irq_domain_map(struct irq_domain *d, unsigned int irq,
> + irq_hw_number_t hwirq)
> +{
> + struct lubbock *cot = d->host_data;
> +
> + irq_set_chip_and_handler(irq, &lubbock_irq_chip, handle_level_irq);
> + irq_set_chip_data(irq, cot);
Again, I'd prefer some separation between code and the return.
(same in all cases below).
> + return 0;
> +}
> +
> +static const struct irq_domain_ops lubbock_irq_domain_ops = {
> + .xlate = irq_domain_xlate_twocell,
> + .map = lubbock_irq_domain_map,
> +};
> +
> +static int lubbock_resume(struct platform_device *pdev)
> +{
> + struct lubbock *cot = platform_get_drvdata(pdev);
> +
> + writel(cot->irq_mask, cot->base + COT_IRQ_MASK_EN);
> + return 0;
> +}
> +
> +static int lubbock_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct lubbock *cot;
> + int ret;
> + unsigned int base_irq = 0;
> + unsigned long irqflags;
> +
> + cot = devm_kzalloc(&pdev->dev, sizeof(*cot), GFP_KERNEL);
> + if (!cot)
> + return -ENOMEM;
'\n' here.
> + res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
platform_get_irq()?
> + if (res) {
> + cot->irq = (unsigned int)res->start;
> + irqflags = res->flags;
> + }
> + if (!cot->irq)
> + return -ENODEV;
> +
> + res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
platform_get_irq()?
> + if (res)
> + base_irq = (unsigned int)res->start;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + cot->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(cot->base))
> + return PTR_ERR(cot->base);
> +
> + platform_set_drvdata(pdev, cot);
> +
> + writel(cot->irq_mask, cot->base + COT_IRQ_MASK_EN);
> + writel(0, cot->base + COT_IRQ_SET_CLR);
'\n'
> + ret = devm_request_irq(&pdev->dev, cot->irq, lubbock_irq_handler,
> + irqflags, dev_name(&pdev->dev), cot);
> + if (ret == -ENOSYS)
> + return -EPROBE_DEFER;
I haven't seen anyone do this after devm_request_irq() before.
Why is it required here?
> + if (ret) {
> + dev_err(&pdev->dev, "Couldn't request main irq : ret = %d\n",
> + ret);
I'm not keen on this type of formatting. Besides the system will
print out the returned error on failure.
> + return ret;
> + }
> + irq_set_irq_wake(cot->irq, 1);
> +
> + cot->irqdomain =
> + irq_domain_add_linear(pdev->dev.of_node, LUBBOCK_NB_IRQ,
> + &lubbock_irq_domain_ops, cot);
As a personal preference, I would prefer to see:
cot->irqdomain = irq_domain_add_linear(pdev->dev.of_node,
LUBBOCK_NB_IRQ,
&lubbock_irq_domain_ops, cot);
> + if (!cot->irqdomain)
> + return -ENODEV;
> +
> + ret = 0;
'ret' will be zero here, or we would have returned already.
> + if (base_irq)
> + ret = irq_create_strict_mappings(cot->irqdomain, base_irq, 0,
> + LUBBOCK_NB_IRQ);
> + if (ret) {
> + dev_err(&pdev->dev, "Couldn't create the irq mapping %d..%d\n",
> + base_irq, base_irq + LUBBOCK_NB_IRQ);
> + return ret;
> + }
Is this solely the check from irq_create_strict_mappings(), therefore
it should be inside the previous if () { ... }.
> + dev_info(&pdev->dev, "base=%p, irq=%d, base_irq=%d\n",
> + cot->base, cot->irq, base_irq);
Please remove this line.
> + return 0;
> +}
> +
> +static int lubbock_remove(struct platform_device *pdev)
> +{
> + struct lubbock *cot = platform_get_drvdata(pdev);
> +
> + irq_set_chip_and_handler(cot->irq, NULL, NULL);
> + return 0;
> +}
> +
> +static const struct of_device_id lubbock_id_table[] = {
> + { .compatible = "intel,lubbock-io", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, lubbock_id_table);
> +
> +static struct platform_driver lubbock_driver = {
> + .driver = {
> + .name = "lubbock_io",
> + .of_match_table = of_match_ptr(lubbock_id_table),
> + },
> + .probe = lubbock_probe,
> + .remove = lubbock_remove,
> + .resume = lubbock_resume,
> +};
> +
> +module_platform_driver(lubbock_driver);
> +
> +MODULE_DESCRIPTION("Lubbock driver");
"Lubbock MFD Driver"?
> +MODULE_AUTHOR("Robert Jarzmik");
Email.
> +MODULE_LICENSE("GPL");
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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