diff options
Diffstat (limited to 'drivers/gpio/gpio-xgene-sb.c')
| -rw-r--r-- | drivers/gpio/gpio-xgene-sb.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-xgene-sb.c b/drivers/gpio/gpio-xgene-sb.c new file mode 100644 index 00000000000..b6a15c39293 --- /dev/null +++ b/drivers/gpio/gpio-xgene-sb.c @@ -0,0 +1,160 @@ +/* + * AppliedMicro X-Gene SoC GPIO-Standby Driver + * + * Copyright (c) 2014, Applied Micro Circuits Corporation + * Author: Tin Huynh <tnhuynh@apm.com>. + * Y Vo <yvo@apm.com>. + * + * 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. + * + * 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/io.h> +#include <linux/platform_device.h> +#include <linux/of_gpio.h> +#include <linux/gpio.h> +#include <linux/gpio/driver.h> +#include <linux/basic_mmio_gpio.h> + +#define XGENE_MAX_GPIO_DS 22 +#define XGENE_MAX_GPIO_DS_IRQ 6 + +#define GPIO_MASK(x) (1U << ((x) % 32)) + +#define MPA_GPIO_INT_LVL 0x0290 +#define MPA_GPIO_OE_ADDR 0x029c +#define MPA_GPIO_OUT_ADDR 0x02a0 +#define MPA_GPIO_IN_ADDR 0x02a4 +#define MPA_GPIO_SEL_LO 0x0294 + +/** + * struct xgene_gpio_sb - GPIO-Standby private data structure. + * @bgc: memory-mapped GPIO controllers. + * @irq: Mapping GPIO pins and interrupt number + * nirq: Number of GPIO pins that supports interrupt + */ +struct xgene_gpio_sb { + struct bgpio_chip bgc; + u32 *irq; + u32 nirq; +}; + +static inline struct xgene_gpio_sb *to_xgene_gpio_sb(struct gpio_chip *gc) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + + return container_of(bgc, struct xgene_gpio_sb, bgc); +} + +static void xgene_gpio_set_bit(struct bgpio_chip *bgc, void __iomem *reg, u32 gpio, int val) +{ + u32 data; + + data = bgc->read_reg(reg); + if (val) + data |= GPIO_MASK(gpio); + else + data &= ~GPIO_MASK(gpio); + bgc->write_reg(reg, data); +} + +static int apm_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio) +{ + struct xgene_gpio_sb *priv = to_xgene_gpio_sb(gc); + + if (priv->irq[gpio]) + return priv->irq[gpio]; + + return -ENXIO; +} + +static int xgene_gpio_sb_probe(struct platform_device *pdev) +{ + struct xgene_gpio_sb *priv; + u32 ret, i; + u32 default_lines[] = {0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D}; + struct resource *res; + void __iomem *regs; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + regs = devm_ioremap_resource(&pdev->dev, res); + if (!regs) + return PTR_ERR(regs); + + ret = bgpio_init(&priv->bgc, &pdev->dev, 4, + regs + MPA_GPIO_IN_ADDR, + regs + MPA_GPIO_OUT_ADDR, NULL, + regs + MPA_GPIO_OE_ADDR, NULL, 0); + if (ret) + return ret; + + priv->bgc.gc.to_irq = apm_gpio_sb_to_irq; + priv->bgc.gc.ngpio = XGENE_MAX_GPIO_DS; + + priv->nirq = XGENE_MAX_GPIO_DS_IRQ; + + priv->irq = devm_kzalloc(&pdev->dev, sizeof(u32) * XGENE_MAX_GPIO_DS, + GFP_KERNEL); + if (!priv->irq) + return -ENOMEM; + memset(priv->irq, 0, sizeof(u32) * XGENE_MAX_GPIO_DS); + + for (i = 0; i < priv->nirq; i++) { + priv->irq[default_lines[i]] = platform_get_irq(pdev, i); + xgene_gpio_set_bit(&priv->bgc, regs + MPA_GPIO_SEL_LO, + default_lines[i] * 2, 1); + xgene_gpio_set_bit(&priv->bgc, regs + MPA_GPIO_INT_LVL, i, 1); + } + + platform_set_drvdata(pdev, priv); + + ret = gpiochip_add(&priv->bgc.gc); + if (ret) + dev_err(&pdev->dev, "failed to register X-Gene GPIO Standby driver\n"); + else + dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n"); + + return ret; +} + +static int xgene_gpio_sb_remove(struct platform_device *pdev) +{ + struct xgene_gpio_sb *priv = platform_get_drvdata(pdev); + + return bgpio_remove(&priv->bgc); +} + +static const struct of_device_id xgene_gpio_sb_of_match[] = { + {.compatible = "apm,xgene-gpio-sb", }, + {}, +}; +MODULE_DEVICE_TABLE(of, xgene_gpio_sb_of_match); + +static struct platform_driver xgene_gpio_sb_driver = { + .driver = { + .name = "xgene-gpio-sb", + .of_match_table = xgene_gpio_sb_of_match, + }, + .probe = xgene_gpio_sb_probe, + .remove = xgene_gpio_sb_remove, +}; +module_platform_driver(xgene_gpio_sb_driver); + +MODULE_AUTHOR("AppliedMicro"); +MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver"); +MODULE_LICENSE("GPL"); |