2012-05-17 20:50:49

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH 2/2] gpio/MIPS/OCTEON: Add a driver for OCTEON's on-chip GPIO pins.

On Thu, 12 Apr 2012 17:10:20 -0700, David Daney <[email protected]> wrote:
> From: David Daney <[email protected]>
>
> The SOCs in the OCTEON family have 16 (or in some cases 20) on-chip
> GPIO pins, this driver handles them all. Configuring the pins as
> interrupt sources is handled elsewhere (OCTEON's irq handling code).
>
> Signed-off-by: David Daney <[email protected]>

Aside from the bugs already pointed out;

Acked-by: Grant Likely <[email protected]>

Will you merge this series via the MIPS tree, or do I need to pick it
up?

> ---
> drivers/gpio/Kconfig | 8 ++
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-octeon.c | 166 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 175 insertions(+), 0 deletions(-)
> create mode 100644 drivers/gpio/gpio-octeon.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index edadbda..d9d924c 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -136,6 +136,14 @@ config GPIO_MXS
> select GPIO_GENERIC
> select GENERIC_IRQ_CHIP
>
> +config GPIO_OCTEON
> + tristate "Cavium OCTEON GPIO"
> + depends on GPIOLIB && CPU_CAVIUM_OCTEON
> + default y
> + help
> + Say yes here to support the on-chip GPIO lines on the OCTEON
> + family of SOCs.
> +
> config GPIO_PL061
> bool "PrimeCell PL061 GPIO support"
> depends on ARM_AMBA
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index 007f54b..ce0348c 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -37,6 +37,7 @@ obj-$(CONFIG_GPIO_MSM_V2) += gpio-msm-v2.o
> obj-$(CONFIG_GPIO_MXC) += gpio-mxc.o
> obj-$(CONFIG_GPIO_MXS) += gpio-mxs.o
> obj-$(CONFIG_PLAT_NOMADIK) += gpio-nomadik.o
> +obj-$(CONFIG_GPIO_OCTEON) += gpio-octeon.o
> obj-$(CONFIG_ARCH_OMAP) += gpio-omap.o
> obj-$(CONFIG_GPIO_PCA953X) += gpio-pca953x.o
> obj-$(CONFIG_GPIO_PCF857X) += gpio-pcf857x.o
> diff --git a/drivers/gpio/gpio-octeon.c b/drivers/gpio/gpio-octeon.c
> new file mode 100644
> index 0000000..e679b44
> --- /dev/null
> +++ b/drivers/gpio/gpio-octeon.c
> @@ -0,0 +1,166 @@
> +/*
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License. See the file "COPYING" in the main directory of this archive
> + * for more details.
> + *
> + * Copyright (C) 2011,2012 Cavium Inc.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/gpio.h>
> +#include <linux/io.h>
> +
> +#include <asm/octeon/octeon.h>
> +#include <asm/octeon/cvmx-gpio-defs.h>
> +
> +#define DRV_VERSION "1.0"
> +#define DRV_DESCRIPTION "Cavium Inc. OCTEON GPIO Driver"
> +
> +#define RX_DAT 0x80
> +#define TX_SET 0x88
> +#define TX_CLEAR 0x90
> +/*
> + * The address offset of the GPIO configuration register for a given
> + * line.
> + */
> +static unsigned int bit_cfg_reg(unsigned int gpio)
> +{
> + if (gpio < 16)
> + return 8 * gpio;
> + else
> + return 8 * (gpio - 16) + 0x100;
> +}
> +
> +struct octeon_gpio {
> + struct gpio_chip chip;
> + u64 register_base;
> +};
> +
> +static int octeon_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
> +{
> + struct octeon_gpio *gpio = container_of(chip, struct octeon_gpio, chip);
> +
> + cvmx_write_csr(gpio->register_base + bit_cfg_reg(offset), 0);
> + return 0;
> +}
> +
> +static void octeon_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
> +{
> + struct octeon_gpio *gpio = container_of(chip, struct octeon_gpio, chip);
> + u64 mask = 1ull << offset;
> + u64 reg = gpio->register_base + (value ? TX_SET : TX_CLEAR);
> + cvmx_write_csr(reg, mask);
> +}
> +
> +static int octeon_gpio_dir_out(struct gpio_chip *chip, unsigned offset,
> + int value)
> +{
> + struct octeon_gpio *gpio = container_of(chip, struct octeon_gpio, chip);
> + union cvmx_gpio_bit_cfgx cfgx;
> +
> +
> + octeon_gpio_set(chip, offset, value);
> +
> + cfgx.u64 = 0;
> + cfgx.s.tx_oe = 1;
> +
> + cvmx_write_csr(gpio->register_base + bit_cfg_reg(offset), cfgx.u64);
> + return 0;
> +}
> +
> +static int octeon_gpio_get(struct gpio_chip *chip, unsigned offset)
> +{
> + struct octeon_gpio *gpio = container_of(chip, struct octeon_gpio, chip);
> + u64 read_bits = cvmx_read_csr(gpio->register_base + RX_DAT);
> +
> + return ((1ull << offset) & read_bits) != 0;
> +}
> +
> +static int __init octeon_gpio_probe(struct platform_device *pdev)
> +{
> + struct octeon_gpio *gpio;
> + struct gpio_chip *chip;
> + struct resource *res_mem;
> + int err = 0;
> +
> + gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
> + if (!gpio)
> + return -ENOMEM;
> + chip = &gpio->chip;
> +
> + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (res_mem == NULL) {
> + dev_err(&pdev->dev, "found no memory resource\n");
> + err = -ENXIO;
> + goto out;
> + }
> + if (!devm_request_mem_region(&pdev->dev, res_mem->start,
> + resource_size(res_mem),
> + res_mem->name)) {
> + dev_err(&pdev->dev, "request_mem_region failed\n");
> + err = -ENXIO;
> + goto out;
> + }
> + gpio->register_base = (u64)devm_ioremap(&pdev->dev, res_mem->start,
> + resource_size(res_mem));
> +
> +
> + pdev->dev.platform_data = chip;
> + chip->label = "octeon-gpio";
> + chip->dev = &pdev->dev;
> + chip->owner = THIS_MODULE;
> + chip->base = 0;
> + chip->can_sleep = 0;
> +
> + if (OCTEON_IS_MODEL(OCTEON_CN66XX) ||
> + OCTEON_IS_MODEL(OCTEON_CN61XX) ||
> + OCTEON_IS_MODEL(OCTEON_CNF71XX))
> + chip->ngpio = 20;
> + else
> + chip->ngpio = 16;
> +
> + chip->direction_input = octeon_gpio_dir_in;
> + chip->get = octeon_gpio_get;
> + chip->direction_output = octeon_gpio_dir_out;
> + chip->set = octeon_gpio_set;
> + err = gpiochip_add(chip);
> + if (err)
> + goto out;
> +
> + dev_info(&pdev->dev, "version: " DRV_VERSION "\n");
> +out:
> + return err;
> +}
> +
> +static int __exit octeon_gpio_remove(struct platform_device *pdev)
> +{
> + struct gpio_chip *chip = pdev->dev.platform_data;
> + return gpiochip_remove(chip);
> +}
> +
> +static struct of_device_id octeon_gpio_match[] = {
> + {
> + .compatible = "cavium,octeon-3860-gpio",
> + },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, octeon_mgmt_match);
> +
> +static struct platform_driver octeon_gpio_driver = {
> + .driver = {
> + .name = "octeon_gpio",
> + .owner = THIS_MODULE,
> + .of_match_table = octeon_gpio_match,
> + },
> + .probe = octeon_gpio_probe,
> + .remove = __exit_p(octeon_gpio_remove),
> +};
> +
> +module_platform_driver(octeon_gpio_driver);
> +
> +MODULE_DESCRIPTION(DRV_DESCRIPTION);
> +MODULE_AUTHOR("David Daney");
> +MODULE_LICENSE("GPL");
> +MODULE_VERSION(DRV_VERSION);
> --
> 1.7.2.3
>

--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.


2012-05-17 21:37:46

by David Daney

[permalink] [raw]
Subject: Re: [PATCH 2/2] gpio/MIPS/OCTEON: Add a driver for OCTEON's on-chip GPIO pins.

On 05/17/2012 01:50 PM, Grant Likely wrote:
> On Thu, 12 Apr 2012 17:10:20 -0700, David Daney<[email protected]> wrote:
>> From: David Daney<[email protected]>
>>
>> The SOCs in the OCTEON family have 16 (or in some cases 20) on-chip
>> GPIO pins, this driver handles them all. Configuring the pins as
>> interrupt sources is handled elsewhere (OCTEON's irq handling code).
>>
>> Signed-off-by: David Daney<[email protected]>
>
> Aside from the bugs already pointed out;
>
> Acked-by: Grant Likely<[email protected]>
>
> Will you merge this series via the MIPS tree, or do I need to pick it
> up?

Thanks Grant.

I will make the fixes and resubmit. I expect Ralf can merge these along
with the rest of the pile of OCTEON patches.

David Daney

>
>> ---
>> drivers/gpio/Kconfig | 8 ++
>> drivers/gpio/Makefile | 1 +
>> drivers/gpio/gpio-octeon.c | 166 ++++++++++++++++++++++++++++++++++++++++++++