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-rw-r--r--drivers/i2c/busses/i2c-pca-platform.c255
1 files changed, 255 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c
new file mode 100644
index 000000000..86d4f75ef
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pca-platform.c
@@ -0,0 +1,255 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * i2c_pca_platform.c
+ *
+ * Platform driver for the PCA9564 I2C controller.
+ *
+ * Copyright (C) 2008 Pengutronix
+ *
+
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/jiffies.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/i2c-algo-pca.h>
+#include <linux/platform_data/i2c-pca-platform.h>
+#include <linux/gpio/consumer.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <asm/irq.h>
+
+struct i2c_pca_pf_data {
+ void __iomem *reg_base;
+ int irq; /* if 0, use polling */
+ struct gpio_desc *gpio;
+ wait_queue_head_t wait;
+ struct i2c_adapter adap;
+ struct i2c_algo_pca_data algo_data;
+};
+
+/* Read/Write functions for different register alignments */
+
+static int i2c_pca_pf_readbyte8(void *pd, int reg)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ return ioread8(i2c->reg_base + reg);
+}
+
+static int i2c_pca_pf_readbyte16(void *pd, int reg)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ return ioread8(i2c->reg_base + reg * 2);
+}
+
+static int i2c_pca_pf_readbyte32(void *pd, int reg)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ return ioread8(i2c->reg_base + reg * 4);
+}
+
+static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ iowrite8(val, i2c->reg_base + reg);
+}
+
+static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ iowrite8(val, i2c->reg_base + reg * 2);
+}
+
+static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ iowrite8(val, i2c->reg_base + reg * 4);
+}
+
+
+static int i2c_pca_pf_waitforcompletion(void *pd)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+ unsigned long timeout;
+ long ret;
+
+ if (i2c->irq) {
+ ret = wait_event_timeout(i2c->wait,
+ i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
+ & I2C_PCA_CON_SI, i2c->adap.timeout);
+ } else {
+ /* Do polling */
+ timeout = jiffies + i2c->adap.timeout;
+ do {
+ ret = time_before(jiffies, timeout);
+ if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
+ & I2C_PCA_CON_SI)
+ break;
+ udelay(100);
+ } while (ret);
+ }
+
+ return ret > 0;
+}
+
+static void i2c_pca_pf_dummyreset(void *pd)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+
+ dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
+}
+
+static void i2c_pca_pf_resetchip(void *pd)
+{
+ struct i2c_pca_pf_data *i2c = pd;
+
+ gpiod_set_value(i2c->gpio, 1);
+ ndelay(100);
+ gpiod_set_value(i2c->gpio, 0);
+}
+
+static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
+{
+ struct i2c_pca_pf_data *i2c = dev_id;
+
+ if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
+ return IRQ_NONE;
+
+ wake_up(&i2c->wait);
+
+ return IRQ_HANDLED;
+}
+
+
+static int i2c_pca_pf_probe(struct platform_device *pdev)
+{
+ struct i2c_pca_pf_data *i2c;
+ struct resource *res;
+ struct i2c_pca9564_pf_platform_data *platform_data =
+ dev_get_platdata(&pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
+ int ret = 0;
+ int irq;
+
+ irq = platform_get_irq_optional(pdev, 0);
+ /* If irq is 0, we do polling. */
+ if (irq < 0)
+ irq = 0;
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
+ if (!i2c)
+ return -ENOMEM;
+
+ i2c->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(i2c->reg_base))
+ return PTR_ERR(i2c->reg_base);
+
+
+ init_waitqueue_head(&i2c->wait);
+
+ i2c->irq = irq;
+
+ i2c->adap.nr = pdev->id;
+ i2c->adap.owner = THIS_MODULE;
+ snprintf(i2c->adap.name, sizeof(i2c->adap.name),
+ "PCA9564/PCA9665 at 0x%08lx",
+ (unsigned long) res->start);
+ i2c->adap.algo_data = &i2c->algo_data;
+ i2c->adap.dev.parent = &pdev->dev;
+ i2c->adap.dev.of_node = np;
+
+ i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(i2c->gpio))
+ return PTR_ERR(i2c->gpio);
+
+ i2c->adap.timeout = HZ;
+ ret = device_property_read_u32(&pdev->dev, "clock-frequency",
+ &i2c->algo_data.i2c_clock);
+ if (ret)
+ i2c->algo_data.i2c_clock = 59000;
+
+ if (platform_data) {
+ i2c->adap.timeout = platform_data->timeout;
+ i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
+ }
+
+ i2c->algo_data.data = i2c;
+ i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
+ if (i2c->gpio)
+ i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
+ else
+ i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
+
+ switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
+ case IORESOURCE_MEM_32BIT:
+ i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
+ i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
+ break;
+ case IORESOURCE_MEM_16BIT:
+ i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
+ i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
+ break;
+ case IORESOURCE_MEM_8BIT:
+ default:
+ i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
+ i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
+ break;
+ }
+
+ if (irq) {
+ ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
+ IRQF_TRIGGER_FALLING, pdev->name, i2c);
+ if (ret)
+ return ret;
+ }
+
+ ret = i2c_pca_add_numbered_bus(&i2c->adap);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, i2c);
+
+ dev_info(&pdev->dev, "registered.\n");
+
+ return 0;
+}
+
+static int i2c_pca_pf_remove(struct platform_device *pdev)
+{
+ struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id i2c_pca_of_match_table[] = {
+ { .compatible = "nxp,pca9564" },
+ { .compatible = "nxp,pca9665" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
+#endif
+
+static struct platform_driver i2c_pca_pf_driver = {
+ .probe = i2c_pca_pf_probe,
+ .remove = i2c_pca_pf_remove,
+ .driver = {
+ .name = "i2c-pca-platform",
+ .of_match_table = of_match_ptr(i2c_pca_of_match_table),
+ },
+};
+
+module_platform_driver(i2c_pca_pf_driver);
+
+MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
+MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 18:49:02 +0000