On Fri, May 30, 2014 at 4:23 AM, Feng Kan <fkan@xxxxxxx> wrote: > Add APM X-Gene SoC gpio controller driver. > > Signed-off-by: Feng Kan <fkan@xxxxxxx> > --- > drivers/gpio/Kconfig | 9 ++ > drivers/gpio/Makefile | 1 + > drivers/gpio/gpio-xgene.c | 231 ++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 241 insertions(+) > create mode 100644 drivers/gpio/gpio-xgene.c > > diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig > index a86c49a..9a15983 100644 > --- a/drivers/gpio/Kconfig > +++ b/drivers/gpio/Kconfig > @@ -324,6 +324,15 @@ config GPIO_TZ1090_PDC > help > Say yes here to support Toumaz Xenif TZ1090 PDC GPIOs. > > +config GPIO_XGENE > + bool "APM X-Gene GPIO controller support" > + depends on ARM64 && OF_GPIO > + help > + This driver is to support the GPIO block within the APM X-Gene SoC > + platform's generic flash controller. The GPIO pins are muxed with > + the generic flash controller's address and data pins. Say yes > + here to enable the GFC GPIO functionality. > + > config GPIO_XILINX > bool "Xilinx GPIO support" > depends on PPC_OF || MICROBLAZE || ARCH_ZYNQ > diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile > index 6309aff..f0f2830 100644 > --- a/drivers/gpio/Makefile > +++ b/drivers/gpio/Makefile > @@ -98,6 +98,7 @@ obj-$(CONFIG_GPIO_VX855) += gpio-vx855.o > obj-$(CONFIG_GPIO_WM831X) += gpio-wm831x.o > obj-$(CONFIG_GPIO_WM8350) += gpio-wm8350.o > obj-$(CONFIG_GPIO_WM8994) += gpio-wm8994.o > +obj-$(CONFIG_GPIO_XGENE) += gpio-xgene.o > obj-$(CONFIG_GPIO_XILINX) += gpio-xilinx.o > obj-$(CONFIG_GPIO_XTENSA) += gpio-xtensa.o > obj-$(CONFIG_GPIO_ZEVIO) += gpio-zevio.o > diff --git a/drivers/gpio/gpio-xgene.c b/drivers/gpio/gpio-xgene.c > new file mode 100644 > index 0000000..a542f76 > --- /dev/null > +++ b/drivers/gpio/gpio-xgene.c > @@ -0,0 +1,231 @@ > +/* > + * AppliedMicro X-Gene SoC GPIO Driver > + * > + * Copyright (c) 2014, Applied Micro Circuits Corporation > + * Author: Feng Kan <fkan@xxxxxxx>. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see <http://www.gnu.org/licenses/>. > + */ > + > +#include <linux/module.h> > +#include <linux/kernel.h> > +#include <linux/init.h> > +#include <linux/io.h> > +#include <linux/spinlock.h> > +#include <linux/platform_device.h> > +#include <linux/of_gpio.h> > +#include <linux/of.h> > +#include <linux/gpio.h> > +#include <linux/types.h> > +#include <linux/slab.h> > +#include <linux/clk.h> > +#include <linux/bitops.h> > + > +#define GPIO_SET_MASK(x) BIT(x + 16) > + > +#define GPIO_SET_DR_OFFSET 0x00 > +#define GPIO_DATA_OFFSET 0x08 > + > +#define XGENE_MAX_GPIO_PER_BANK 16 > + > +struct xgene_gpio; > + > +struct xgene_gpio { > + struct device *dev; > + struct xgene_gpio_bank *banks; I am not seeing this member being used at all in your driver, apart from being kzalloc'd. > + struct gpio_chip chip; > + void __iomem *base; > + spinlock_t lock; > +#ifdef CONFIG_PM > + u32 set_dr_val; > + u32 od_val; > +#endif > +}; > + > +static inline struct xgene_gpio *to_xgene_gpio(struct gpio_chip *chip) > +{ > + return container_of(chip, struct xgene_gpio, chip); > +} > + > +static int xgene_gpio_get(struct gpio_chip *gc, unsigned int offset) > +{ > + struct xgene_gpio *bank = to_xgene_gpio(gc); > + > + return !!(ioread32(bank->base + GPIO_DATA_OFFSET) & BIT(offset)); > +} > + > +static void xgene_gpio_set(struct gpio_chip *gc, unsigned int offset, int val) > +{ > + struct xgene_gpio *bank = to_xgene_gpio(gc); > + unsigned long flags; > + u32 setval; > + > + spin_lock_irqsave(&bank->lock, flags); > + > + setval = ioread32(bank->base + GPIO_SET_DR_OFFSET); > + if (val) > + setval |= GPIO_SET_MASK(offset); > + else > + setval &= ~GPIO_SET_MASK(offset); Let's use __set_bit and __clear_bit here and everywhere it applies. > + iowrite32(setval, bank->base + GPIO_SET_DR_OFFSET); > + > + spin_unlock_irqrestore(&bank->lock, flags); > +} > + > +static int xgene_gpio_dir_in(struct gpio_chip *gc, unsigned int offset) > +{ > + struct xgene_gpio *bank = to_xgene_gpio(gc); > + unsigned long flags; > + u32 dirval; > + > + spin_lock_irqsave(&bank->lock, flags); > + > + dirval = ioread32(bank->base + GPIO_SET_DR_OFFSET); > + dirval |= BIT(offset); > + iowrite32(dirval, bank->base + GPIO_SET_DR_OFFSET); > + > + spin_unlock_irqrestore(&bank->lock, flags); > + > + return 0; > +} > + > +static int xgene_gpio_dir_out(struct gpio_chip *gc, > + unsigned int offset, int val) > +{ > + struct xgene_gpio *bank = to_xgene_gpio(gc); > + unsigned long flags; > + u32 dirval; > + > + spin_lock_irqsave(&bank->lock, flags); > + > + dirval = ioread32(bank->base + GPIO_SET_DR_OFFSET); > + dirval &= ~BIT(offset); > + iowrite32(dirval, bank->base + GPIO_SET_DR_OFFSET); > + > + spin_unlock_irqrestore(&bank->lock, flags); > + > + return 0; > +} > + > +#ifdef CONFIG_PM > +static int xgene_gpio_suspend(struct device *dev) > +{ > + struct xgene_gpio *gpio = dev_get_drvdata(dev); > + > + gpio->set_dr_val = ioread32(gpio->base + GPIO_SET_DR_OFFSET); > + return 0; > +} > + > +static int xgene_gpio_resume(struct device *dev) > +{ > + struct xgene_gpio *gpio = dev_get_drvdata(dev); > + > + iowrite32(gpio->set_dr_val, gpio->base + GPIO_SET_DR_OFFSET); > + return 0; > +} > + > +static SIMPLE_DEV_PM_OPS(xgene_gpio_pm, xgene_gpio_suspend, xgene_gpio_resume); > +#define XGENE_GPIO_PM_OPS (&xgene_gpio_pm) > +#else > +#define XGENE_GPIO_PM_OPS NULL > +#endif > + > +static int xgene_gpio_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct resource *res; > + struct xgene_gpio *gpio; > + int err = 0; > + unsigned int bank = 0, ngpio = 0; > + > + gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); > + if (!gpio) { > + err = -ENOMEM; > + goto err; > + } > + gpio->dev = &pdev->dev; > + > + gpio->banks = devm_kzalloc(&pdev->dev, > + sizeof(struct xgene_gpio), GFP_KERNEL); > + if (!gpio->banks) { > + err = -ENOMEM; > + goto err; > + } > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + gpio->base = devm_ioremap_nocache(&pdev->dev, res->start, > + resource_size(res)); > + if (IS_ERR(gpio->base)) { > + err = PTR_ERR(gpio->base); > + goto err; > + } > + > + /* > + * Determine gpio bank using gpio resource address > + */ > + bank = (res->start & 0xff) / 0xc - 1; > + if (bank > 2) { > + dev_err(gpio->dev, "incorrect gpio base specified\n"); > + goto err; > + } > + > + ngpio = XGENE_MAX_GPIO_PER_BANK; > + gpio->chip.ngpio = ngpio; Maybe use XGENE_MAX_GPIO_PER_BANK directly instead of ngpio which is not used otherwise. > + gpio->chip.of_node = np; > + gpio->chip.base = bank * ngpio; This is dangerous. You are assuming that your chip will be the first GPIO chip to be registered. Can't you leave chip.base uninitialized? > + gpio->chip.label = dev_name(&pdev->dev); > + > + gpio->chip.direction_input = xgene_gpio_dir_in; > + gpio->chip.direction_output = xgene_gpio_dir_out; > + gpio->chip.get = xgene_gpio_get; > + gpio->chip.set = xgene_gpio_set; > + > + platform_set_drvdata(pdev, gpio); > + > + err = gpiochip_add(&gpio->chip); > + if (err) { > + dev_err(gpio->dev, > + "failed to register gpiochip for bank%d\n", bank); > + goto err; > + } > + > + dev_info(&pdev->dev, "X-Gene GPIO driver registered\n"); > + return 0; > +err: > + dev_err(&pdev->dev, "X-Gene GPIO driver registration failed\n"); > + return err; > +} > + > +#ifdef CONFIG_OF > +static const struct of_device_id xgene_gpio_of_match[] = { > + { .compatible = "apm,xgene-gpio", }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, xgene_gpio_of_match); > +#endif > + > +static struct platform_driver xgene_gpio_driver = { > + .driver = { > + .name = "xgene-gpio", > + .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(xgene_gpio_of_match), > + .pm = XGENE_GPIO_PM_OPS, > + }, > + .probe = xgene_gpio_probe, > +}; > + > +module_platform_driver(xgene_gpio_driver); > + > +MODULE_AUTHOR("Feng Kan <fkan@xxxxxxx>"); > +MODULE_DESCRIPTION("APM X-Gene GPIO driver"); > +MODULE_LICENSE("GPL"); > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
