[PATCH 3.4 070/146] ARM: pxa: pxa_cplds: add lubbock and mainstone IO

lizf
2015-09-15T09:09:27Z

From: Robert Jarzmik <robert.jarzmik@free.fr>

3.4.109-rc1 review patch. If anyone has any objections, please let me know.

------------------

commit aa8d6b73ea33c2167c543663ab66039ec94d58f1 upstream.

Historically, this support was in arch/arm/mach-pxa/lubbock.c and
arch/arm/mach-pxa/mainstone.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.

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

The same logic applies to mainstone board.

Fixes: 157d2644cb0c ("ARM: pxa: change gpio to platform device")
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
arch/arm/mach-pxa/Kconfig | 9 ++
arch/arm/mach-pxa/Makefile | 1 +
arch/arm/mach-pxa/pxa_cplds_irqs.c | 200 +++++++++++++++++++++++++++++++++++++
3 files changed, 210 insertions(+)
create mode 100644 arch/arm/mach-pxa/pxa_cplds_irqs.c

diff --git a/arch/arm/mach-pxa/Kconfig b/arch/arm/mach-pxa/Kconfig
index fe2d1f8..2f8b171 100644
--- a/arch/arm/mach-pxa/Kconfig
+++ b/arch/arm/mach-pxa/Kconfig
@@ -718,4 +718,13 @@ config PXA_HAVE_ISA_IRQS
config PXA310_ULPI
bool

+config PXA_SYSTEMS_CPLDS
+ tristate "Motherboard cplds"
+ default ARCH_LUBBOCK || MACH_MAINSTONE
+ help
+ This driver supports the Lubbock and Mainstone multifunction chip
+ found on the pxa25x development platform system (Lubbock) and pxa27x
+ development platform system (Mainstone). This IO board supports the
+ interrupts handling, ethernet controller, flash chips, etc ...
+
endif
diff --git a/arch/arm/mach-pxa/Makefile b/arch/arm/mach-pxa/Makefile
index be0f7df..318c0d7 100644
--- a/arch/arm/mach-pxa/Makefile
+++ b/arch/arm/mach-pxa/Makefile
@@ -103,4 +103,5 @@ led-$(CONFIG_ARCH_PXA_IDP) += leds-idp.o

obj-$(CONFIG_LEDS) += $(led-y)

+obj-$(CONFIG_PXA_SYSTEMS_CPLDS) += pxa_cplds_irqs.o
obj-$(CONFIG_TOSA_BT) += tosa-bt.o
diff --git a/arch/arm/mach-pxa/pxa_cplds_irqs.c b/arch/arm/mach-pxa/pxa_cplds_irqs.c
new file mode 100644
index 0000000..f1aeb54
--- /dev/null
+++ b/arch/arm/mach-pxa/pxa_cplds_irqs.c
@@ -0,0 +1,200 @@
+/*
+ * Intel Reference Systems cplds
+ *
+ * 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.
+ *
+ * Cplds motherboard driver, supporting lubbock and mainstone SoC board.
+ */
+
+#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>
+#include <linux/of_platform.h>
+
+#define FPGA_IRQ_MASK_EN 0x0
+#define FPGA_IRQ_SET_CLR 0x10
+
+#define CPLDS_NB_IRQ 32
+
+struct cplds {
+ void __iomem *base;
+ int irq;
+ unsigned int irq_mask;
+ struct gpio_desc *gpio0;
+ struct irq_domain *irqdomain;
+};
+
+static irqreturn_t cplds_irq_handler(int in_irq, void *d)
+{
+ struct cplds *fpga = d;
+ unsigned long pending;
+ unsigned int bit;
+
+ pending = readl(fpga->base + FPGA_IRQ_SET_CLR) & fpga->irq_mask;
+ for_each_set_bit(bit, &pending, CPLDS_NB_IRQ)
+ generic_handle_irq(irq_find_mapping(fpga->irqdomain, bit));
+
+ return IRQ_HANDLED;
+}
+
+static void cplds_irq_mask_ack(struct irq_data *d)
+{
+ struct cplds *fpga = irq_data_get_irq_chip_data(d);
+ unsigned int cplds_irq = irqd_to_hwirq(d);
+ unsigned int set, bit = BIT(cplds_irq);
+
+ fpga->irq_mask &= ~bit;
+ writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN);
+ set = readl(fpga->base + FPGA_IRQ_SET_CLR);
+ writel(set & ~bit, fpga->base + FPGA_IRQ_SET_CLR);
+}
+
+static void cplds_irq_unmask(struct irq_data *d)
+{
+ struct cplds *fpga = irq_data_get_irq_chip_data(d);
+ unsigned int cplds_irq = irqd_to_hwirq(d);
+ unsigned int bit = BIT(cplds_irq);
+
+ fpga->irq_mask |= bit;
+ writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN);
+}
+
+static struct irq_chip cplds_irq_chip = {
+ .name = "pxa_cplds",
+ .irq_mask_ack = cplds_irq_mask_ack,
+ .irq_unmask = cplds_irq_unmask,
+ .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE,
+};
+
+static int cplds_irq_domain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct cplds *fpga = d->host_data;
+
+ irq_set_chip_and_handler(irq, &cplds_irq_chip, handle_level_irq);
+ irq_set_chip_data(irq, fpga);
+
+ return 0;
+}
+
+static const struct irq_domain_ops cplds_irq_domain_ops = {
+ .xlate = irq_domain_xlate_twocell,
+ .map = cplds_irq_domain_map,
+};
+
+static int cplds_resume(struct platform_device *pdev)
+{
+ struct cplds *fpga = platform_get_drvdata(pdev);
+
+ writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN);
+
+ return 0;
+}
+
+static int cplds_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct cplds *fpga;
+ int ret;
+ unsigned int base_irq = 0;
+ unsigned long irqflags = 0;
+
+ fpga = devm_kzalloc(&pdev->dev, sizeof(*fpga), GFP_KERNEL);
+ if (!fpga)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (res) {
+ fpga->irq = (unsigned int)res->start;
+ irqflags = res->flags;
+ }
+ if (!fpga->irq)
+ return -ENODEV;
+
+ base_irq = platform_get_irq(pdev, 1);
+ if (base_irq < 0)
+ base_irq = 0;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ fpga->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(fpga->base))
+ return PTR_ERR(fpga->base);
+
+ platform_set_drvdata(pdev, fpga);
+
+ writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN);
+ writel(0, fpga->base + FPGA_IRQ_SET_CLR);
+
+ ret = devm_request_irq(&pdev->dev, fpga->irq, cplds_irq_handler,
+ irqflags, dev_name(&pdev->dev), fpga);
+ if (ret == -ENOSYS)
+ return -EPROBE_DEFER;
+
+ if (ret) {
+ dev_err(&pdev->dev, "couldn't request main irq%d: %d\n",
+ fpga->irq, ret);
+ return ret;
+ }
+
+ irq_set_irq_wake(fpga->irq, 1);
+ fpga->irqdomain = irq_domain_add_linear(pdev->dev.of_node,
+ CPLDS_NB_IRQ,
+ &cplds_irq_domain_ops, fpga);
+ if (!fpga->irqdomain)
+ return -ENODEV;
+
+ if (base_irq) {
+ ret = irq_create_strict_mappings(fpga->irqdomain, base_irq, 0,
+ CPLDS_NB_IRQ);
+ if (ret) {
+ dev_err(&pdev->dev, "couldn't create the irq mapping %d..%d\n",
+ base_irq, base_irq + CPLDS_NB_IRQ);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int cplds_remove(struct platform_device *pdev)
+{
+ struct cplds *fpga = platform_get_drvdata(pdev);
+
+ irq_set_chip_and_handler(fpga->irq, NULL, NULL);
+
+ return 0;
+}
+
+static const struct of_device_id cplds_id_table[] = {
+ { .compatible = "intel,lubbock-cplds-irqs", },
+ { .compatible = "intel,mainstone-cplds-irqs", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, cplds_id_table);
+
+static struct platform_driver cplds_driver = {
+ .driver = {
+ .name = "pxa_cplds_irqs",
+ .of_match_table = of_match_ptr(cplds_id_table),
+ },
+ .probe = cplds_probe,
+ .remove = cplds_remove,
+ .resume = cplds_resume,
+};
+
+module_platform_driver(cplds_driver);
+
+MODULE_DESCRIPTION("PXA Cplds interrupts driver");
+MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
+MODULE_LICENSE("GPL");
--
1.9.1