gpio: Add APM X-Gene standby GPIO controller driver
Driver for standby GPIO controller of APM X-Gene SoCs on arm64.
Signed-off-by: Y Vo <yvo@apm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-xgene-sb.c b/drivers/gpio/gpio-xgene-sb.c
new file mode 100644
index 0000000..b6a15c3
--- /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");