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-rw-r--r--drivers/mfd/stmfx.c565
1 files changed, 565 insertions, 0 deletions
diff --git a/drivers/mfd/stmfx.c b/drivers/mfd/stmfx.c
new file mode 100644
index 000000000..b1ecd85ad
--- /dev/null
+++ b/drivers/mfd/stmfx.c
@@ -0,0 +1,565 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for STMicroelectronics Multi-Function eXpander (STMFX) core
+ *
+ * Copyright (C) 2019 STMicroelectronics
+ * Author(s): Amelie Delaunay <amelie.delaunay@st.com>.
+ */
+#include <linux/bitfield.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/stmfx.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+
+static bool stmfx_reg_volatile(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case STMFX_REG_SYS_CTRL:
+ case STMFX_REG_IRQ_SRC_EN:
+ case STMFX_REG_IRQ_PENDING:
+ case STMFX_REG_IRQ_GPI_PENDING1:
+ case STMFX_REG_IRQ_GPI_PENDING2:
+ case STMFX_REG_IRQ_GPI_PENDING3:
+ case STMFX_REG_GPIO_STATE1:
+ case STMFX_REG_GPIO_STATE2:
+ case STMFX_REG_GPIO_STATE3:
+ case STMFX_REG_IRQ_GPI_SRC1:
+ case STMFX_REG_IRQ_GPI_SRC2:
+ case STMFX_REG_IRQ_GPI_SRC3:
+ case STMFX_REG_GPO_SET1:
+ case STMFX_REG_GPO_SET2:
+ case STMFX_REG_GPO_SET3:
+ case STMFX_REG_GPO_CLR1:
+ case STMFX_REG_GPO_CLR2:
+ case STMFX_REG_GPO_CLR3:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool stmfx_reg_writeable(struct device *dev, unsigned int reg)
+{
+ return (reg >= STMFX_REG_SYS_CTRL);
+}
+
+static const struct regmap_config stmfx_regmap_config = {
+ .reg_bits = 8,
+ .reg_stride = 1,
+ .val_bits = 8,
+ .max_register = STMFX_REG_MAX,
+ .volatile_reg = stmfx_reg_volatile,
+ .writeable_reg = stmfx_reg_writeable,
+ .cache_type = REGCACHE_RBTREE,
+};
+
+static const struct resource stmfx_pinctrl_resources[] = {
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_GPIO),
+};
+
+static const struct resource stmfx_idd_resources[] = {
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_IDD),
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_ERROR),
+};
+
+static const struct resource stmfx_ts_resources[] = {
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_DET),
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_NE),
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_TH),
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_FULL),
+ DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_OVF),
+};
+
+static struct mfd_cell stmfx_cells[] = {
+ {
+ .of_compatible = "st,stmfx-0300-pinctrl",
+ .name = "stmfx-pinctrl",
+ .resources = stmfx_pinctrl_resources,
+ .num_resources = ARRAY_SIZE(stmfx_pinctrl_resources),
+ },
+ {
+ .of_compatible = "st,stmfx-0300-idd",
+ .name = "stmfx-idd",
+ .resources = stmfx_idd_resources,
+ .num_resources = ARRAY_SIZE(stmfx_idd_resources),
+ },
+ {
+ .of_compatible = "st,stmfx-0300-ts",
+ .name = "stmfx-ts",
+ .resources = stmfx_ts_resources,
+ .num_resources = ARRAY_SIZE(stmfx_ts_resources),
+ },
+};
+
+static u8 stmfx_func_to_mask(u32 func)
+{
+ u8 mask = 0;
+
+ if (func & STMFX_FUNC_GPIO)
+ mask |= STMFX_REG_SYS_CTRL_GPIO_EN;
+
+ if ((func & STMFX_FUNC_ALTGPIO_LOW) || (func & STMFX_FUNC_ALTGPIO_HIGH))
+ mask |= STMFX_REG_SYS_CTRL_ALTGPIO_EN;
+
+ if (func & STMFX_FUNC_TS)
+ mask |= STMFX_REG_SYS_CTRL_TS_EN;
+
+ if (func & STMFX_FUNC_IDD)
+ mask |= STMFX_REG_SYS_CTRL_IDD_EN;
+
+ return mask;
+}
+
+int stmfx_function_enable(struct stmfx *stmfx, u32 func)
+{
+ u32 sys_ctrl;
+ u8 mask;
+ int ret;
+
+ ret = regmap_read(stmfx->map, STMFX_REG_SYS_CTRL, &sys_ctrl);
+ if (ret)
+ return ret;
+
+ /*
+ * IDD and TS have priority in STMFX FW, so if IDD and TS are enabled,
+ * ALTGPIO function is disabled by STMFX FW. If IDD or TS is enabled,
+ * the number of aGPIO available decreases. To avoid GPIO management
+ * disturbance, abort IDD or TS function enable in this case.
+ */
+ if (((func & STMFX_FUNC_IDD) || (func & STMFX_FUNC_TS)) &&
+ (sys_ctrl & STMFX_REG_SYS_CTRL_ALTGPIO_EN)) {
+ dev_err(stmfx->dev, "ALTGPIO function already enabled\n");
+ return -EBUSY;
+ }
+
+ /* If TS is enabled, aGPIO[3:0] cannot be used */
+ if ((func & STMFX_FUNC_ALTGPIO_LOW) &&
+ (sys_ctrl & STMFX_REG_SYS_CTRL_TS_EN)) {
+ dev_err(stmfx->dev, "TS in use, aGPIO[3:0] unavailable\n");
+ return -EBUSY;
+ }
+
+ /* If IDD is enabled, aGPIO[7:4] cannot be used */
+ if ((func & STMFX_FUNC_ALTGPIO_HIGH) &&
+ (sys_ctrl & STMFX_REG_SYS_CTRL_IDD_EN)) {
+ dev_err(stmfx->dev, "IDD in use, aGPIO[7:4] unavailable\n");
+ return -EBUSY;
+ }
+
+ mask = stmfx_func_to_mask(func);
+
+ return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, mask);
+}
+EXPORT_SYMBOL_GPL(stmfx_function_enable);
+
+int stmfx_function_disable(struct stmfx *stmfx, u32 func)
+{
+ u8 mask = stmfx_func_to_mask(func);
+
+ return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, 0);
+}
+EXPORT_SYMBOL_GPL(stmfx_function_disable);
+
+static void stmfx_irq_bus_lock(struct irq_data *data)
+{
+ struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
+
+ mutex_lock(&stmfx->lock);
+}
+
+static void stmfx_irq_bus_sync_unlock(struct irq_data *data)
+{
+ struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
+
+ regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, stmfx->irq_src);
+
+ mutex_unlock(&stmfx->lock);
+}
+
+static void stmfx_irq_mask(struct irq_data *data)
+{
+ struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
+
+ stmfx->irq_src &= ~BIT(data->hwirq % 8);
+}
+
+static void stmfx_irq_unmask(struct irq_data *data)
+{
+ struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
+
+ stmfx->irq_src |= BIT(data->hwirq % 8);
+}
+
+static struct irq_chip stmfx_irq_chip = {
+ .name = "stmfx-core",
+ .irq_bus_lock = stmfx_irq_bus_lock,
+ .irq_bus_sync_unlock = stmfx_irq_bus_sync_unlock,
+ .irq_mask = stmfx_irq_mask,
+ .irq_unmask = stmfx_irq_unmask,
+};
+
+static irqreturn_t stmfx_irq_handler(int irq, void *data)
+{
+ struct stmfx *stmfx = data;
+ unsigned long bits;
+ u32 pending, ack;
+ int n, ret;
+
+ ret = regmap_read(stmfx->map, STMFX_REG_IRQ_PENDING, &pending);
+ if (ret)
+ return IRQ_NONE;
+
+ /*
+ * There is no ACK for GPIO, MFX_REG_IRQ_PENDING_GPIO is a logical OR
+ * of MFX_REG_IRQ_GPI _PENDING1/_PENDING2/_PENDING3
+ */
+ ack = pending & ~BIT(STMFX_REG_IRQ_SRC_EN_GPIO);
+ if (ack) {
+ ret = regmap_write(stmfx->map, STMFX_REG_IRQ_ACK, ack);
+ if (ret)
+ return IRQ_NONE;
+ }
+
+ bits = pending;
+ for_each_set_bit(n, &bits, STMFX_REG_IRQ_SRC_MAX)
+ handle_nested_irq(irq_find_mapping(stmfx->irq_domain, n));
+
+ return IRQ_HANDLED;
+}
+
+static int stmfx_irq_map(struct irq_domain *d, unsigned int virq,
+ irq_hw_number_t hwirq)
+{
+ irq_set_chip_data(virq, d->host_data);
+ irq_set_chip_and_handler(virq, &stmfx_irq_chip, handle_simple_irq);
+ irq_set_nested_thread(virq, 1);
+ irq_set_noprobe(virq);
+
+ return 0;
+}
+
+static void stmfx_irq_unmap(struct irq_domain *d, unsigned int virq)
+{
+ irq_set_chip_and_handler(virq, NULL, NULL);
+ irq_set_chip_data(virq, NULL);
+}
+
+static const struct irq_domain_ops stmfx_irq_ops = {
+ .map = stmfx_irq_map,
+ .unmap = stmfx_irq_unmap,
+};
+
+static void stmfx_irq_exit(struct i2c_client *client)
+{
+ struct stmfx *stmfx = i2c_get_clientdata(client);
+ int hwirq;
+
+ for (hwirq = 0; hwirq < STMFX_REG_IRQ_SRC_MAX; hwirq++)
+ irq_dispose_mapping(irq_find_mapping(stmfx->irq_domain, hwirq));
+
+ irq_domain_remove(stmfx->irq_domain);
+}
+
+static int stmfx_irq_init(struct i2c_client *client)
+{
+ struct stmfx *stmfx = i2c_get_clientdata(client);
+ u32 irqoutpin = 0, irqtrigger;
+ int ret;
+
+ stmfx->irq_domain = irq_domain_add_simple(stmfx->dev->of_node,
+ STMFX_REG_IRQ_SRC_MAX, 0,
+ &stmfx_irq_ops, stmfx);
+ if (!stmfx->irq_domain) {
+ dev_err(stmfx->dev, "Failed to create IRQ domain\n");
+ return -EINVAL;
+ }
+
+ if (!of_property_read_bool(stmfx->dev->of_node, "drive-open-drain"))
+ irqoutpin |= STMFX_REG_IRQ_OUT_PIN_TYPE;
+
+ irqtrigger = irq_get_trigger_type(client->irq);
+ if ((irqtrigger & IRQ_TYPE_EDGE_RISING) ||
+ (irqtrigger & IRQ_TYPE_LEVEL_HIGH))
+ irqoutpin |= STMFX_REG_IRQ_OUT_PIN_POL;
+
+ ret = regmap_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN, irqoutpin);
+ if (ret)
+ goto irq_exit;
+
+ ret = devm_request_threaded_irq(stmfx->dev, client->irq,
+ NULL, stmfx_irq_handler,
+ irqtrigger | IRQF_ONESHOT,
+ "stmfx", stmfx);
+ if (ret)
+ goto irq_exit;
+
+ stmfx->irq = client->irq;
+
+ return 0;
+
+irq_exit:
+ stmfx_irq_exit(client);
+
+ return ret;
+}
+
+static int stmfx_chip_reset(struct stmfx *stmfx)
+{
+ int ret;
+
+ ret = regmap_write(stmfx->map, STMFX_REG_SYS_CTRL,
+ STMFX_REG_SYS_CTRL_SWRST);
+ if (ret)
+ return ret;
+
+ msleep(STMFX_BOOT_TIME_MS);
+
+ return ret;
+}
+
+static int stmfx_chip_init(struct i2c_client *client)
+{
+ struct stmfx *stmfx = i2c_get_clientdata(client);
+ u32 id;
+ u8 version[2];
+ int ret;
+
+ stmfx->vdd = devm_regulator_get_optional(&client->dev, "vdd");
+ ret = PTR_ERR_OR_ZERO(stmfx->vdd);
+ if (ret) {
+ stmfx->vdd = NULL;
+ if (ret != -ENODEV)
+ return dev_err_probe(&client->dev, ret, "Failed to get VDD regulator\n");
+ }
+
+ if (stmfx->vdd) {
+ ret = regulator_enable(stmfx->vdd);
+ if (ret) {
+ dev_err(&client->dev, "VDD enable failed: %d\n", ret);
+ return ret;
+ }
+ }
+
+ ret = regmap_read(stmfx->map, STMFX_REG_CHIP_ID, &id);
+ if (ret) {
+ dev_err(&client->dev, "Error reading chip ID: %d\n", ret);
+ goto err;
+ }
+
+ /*
+ * Check that ID is the complement of the I2C address:
+ * STMFX I2C address follows the 7-bit format (MSB), that's why
+ * client->addr is shifted.
+ *
+ * STMFX_I2C_ADDR| STMFX | Linux
+ * input pin | I2C device address | I2C device address
+ *---------------------------------------------------------
+ * 0 | b: 1000 010x h:0x84 | 0x42
+ * 1 | b: 1000 011x h:0x86 | 0x43
+ */
+ if (FIELD_GET(STMFX_REG_CHIP_ID_MASK, ~id) != (client->addr << 1)) {
+ dev_err(&client->dev, "Unknown chip ID: %#x\n", id);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ ret = regmap_bulk_read(stmfx->map, STMFX_REG_FW_VERSION_MSB,
+ version, ARRAY_SIZE(version));
+ if (ret) {
+ dev_err(&client->dev, "Error reading FW version: %d\n", ret);
+ goto err;
+ }
+
+ dev_info(&client->dev, "STMFX id: %#x, fw version: %x.%02x\n",
+ id, version[0], version[1]);
+
+ ret = stmfx_chip_reset(stmfx);
+ if (ret) {
+ dev_err(&client->dev, "Failed to reset chip: %d\n", ret);
+ goto err;
+ }
+
+ return 0;
+
+err:
+ if (stmfx->vdd)
+ regulator_disable(stmfx->vdd);
+
+ return ret;
+}
+
+static void stmfx_chip_exit(struct i2c_client *client)
+{
+ struct stmfx *stmfx = i2c_get_clientdata(client);
+
+ regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, 0);
+ regmap_write(stmfx->map, STMFX_REG_SYS_CTRL, 0);
+
+ if (stmfx->vdd) {
+ int ret;
+
+ ret = regulator_disable(stmfx->vdd);
+ if (ret)
+ dev_err(&client->dev,
+ "Failed to disable vdd regulator: %pe\n",
+ ERR_PTR(ret));
+ }
+}
+
+static int stmfx_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct stmfx *stmfx;
+ int ret;
+
+ stmfx = devm_kzalloc(dev, sizeof(*stmfx), GFP_KERNEL);
+ if (!stmfx)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, stmfx);
+
+ stmfx->dev = dev;
+
+ stmfx->map = devm_regmap_init_i2c(client, &stmfx_regmap_config);
+ if (IS_ERR(stmfx->map)) {
+ ret = PTR_ERR(stmfx->map);
+ dev_err(dev, "Failed to allocate register map: %d\n", ret);
+ return ret;
+ }
+
+ mutex_init(&stmfx->lock);
+
+ ret = stmfx_chip_init(client);
+ if (ret) {
+ if (ret == -ETIMEDOUT)
+ return -EPROBE_DEFER;
+ return ret;
+ }
+
+ if (client->irq < 0) {
+ dev_err(dev, "Failed to get IRQ: %d\n", client->irq);
+ ret = client->irq;
+ goto err_chip_exit;
+ }
+
+ ret = stmfx_irq_init(client);
+ if (ret)
+ goto err_chip_exit;
+
+ ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
+ stmfx_cells, ARRAY_SIZE(stmfx_cells), NULL,
+ 0, stmfx->irq_domain);
+ if (ret)
+ goto err_irq_exit;
+
+ return 0;
+
+err_irq_exit:
+ stmfx_irq_exit(client);
+err_chip_exit:
+ stmfx_chip_exit(client);
+
+ return ret;
+}
+
+static void stmfx_remove(struct i2c_client *client)
+{
+ stmfx_irq_exit(client);
+
+ stmfx_chip_exit(client);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int stmfx_suspend(struct device *dev)
+{
+ struct stmfx *stmfx = dev_get_drvdata(dev);
+ int ret;
+
+ ret = regmap_raw_read(stmfx->map, STMFX_REG_SYS_CTRL,
+ &stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl));
+ if (ret)
+ return ret;
+
+ ret = regmap_raw_read(stmfx->map, STMFX_REG_IRQ_OUT_PIN,
+ &stmfx->bkp_irqoutpin,
+ sizeof(stmfx->bkp_irqoutpin));
+ if (ret)
+ return ret;
+
+ disable_irq(stmfx->irq);
+
+ if (stmfx->vdd)
+ return regulator_disable(stmfx->vdd);
+
+ return 0;
+}
+
+static int stmfx_resume(struct device *dev)
+{
+ struct stmfx *stmfx = dev_get_drvdata(dev);
+ int ret;
+
+ if (stmfx->vdd) {
+ ret = regulator_enable(stmfx->vdd);
+ if (ret) {
+ dev_err(stmfx->dev,
+ "VDD enable failed: %d\n", ret);
+ return ret;
+ }
+ }
+
+ /* Reset STMFX - supply has been stopped during suspend */
+ ret = stmfx_chip_reset(stmfx);
+ if (ret) {
+ dev_err(stmfx->dev, "Failed to reset chip: %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_raw_write(stmfx->map, STMFX_REG_SYS_CTRL,
+ &stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl));
+ if (ret)
+ return ret;
+
+ ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN,
+ &stmfx->bkp_irqoutpin,
+ sizeof(stmfx->bkp_irqoutpin));
+ if (ret)
+ return ret;
+
+ ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_SRC_EN,
+ &stmfx->irq_src, sizeof(stmfx->irq_src));
+ if (ret)
+ return ret;
+
+ enable_irq(stmfx->irq);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(stmfx_dev_pm_ops, stmfx_suspend, stmfx_resume);
+
+static const struct of_device_id stmfx_of_match[] = {
+ { .compatible = "st,stmfx-0300", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stmfx_of_match);
+
+static struct i2c_driver stmfx_driver = {
+ .driver = {
+ .name = "stmfx-core",
+ .of_match_table = stmfx_of_match,
+ .pm = &stmfx_dev_pm_ops,
+ },
+ .probe = stmfx_probe,
+ .remove = stmfx_remove,
+};
+module_i2c_driver(stmfx_driver);
+
+MODULE_DESCRIPTION("STMFX core driver");
+MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
+MODULE_LICENSE("GPL v2");