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-rw-r--r--drivers/i2c/busses/Kconfig11
-rw-r--r--drivers/i2c/busses/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-nvidia-gpu.c368
-rw-r--r--drivers/i2c/busses/i2c-qcom-geni.c15
-rw-r--r--drivers/usb/typec/ucsi/Kconfig10
-rw-r--r--drivers/usb/typec/ucsi/Makefile2
-rw-r--r--drivers/usb/typec/ucsi/ucsi_ccg.c307
7 files changed, 706 insertions, 8 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 56ccb1ea7da5..f2c681971201 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985
This driver can also be built as a module. If so, the module
will be called i2c-nforce2-s4985.
+config I2C_NVIDIA_GPU
+ tristate "NVIDIA GPU I2C controller"
+ depends on PCI
+ help
+ If you say yes to this option, support will be included for the
+ NVIDIA GPU I2C controller which is used to communicate with the GPU's
+ Type-C controller. This driver can also be built as a module called
+ i2c-nvidia-gpu.
+
config I2C_SIS5595
tristate "SiS 5595"
depends on PCI
@@ -752,7 +761,7 @@ config I2C_OCORES
config I2C_OMAP
tristate "OMAP I2C adapter"
- depends on ARCH_OMAP
+ depends on ARCH_OMAP || ARCH_K3
default y if MACH_OMAP_H3 || MACH_OMAP_OSK
help
If you say yes to this option, support will be included for the
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 18b26af82b1c..5f0cb6915969 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_I2C_ISCH) += i2c-isch.o
obj-$(CONFIG_I2C_ISMT) += i2c-ismt.o
obj-$(CONFIG_I2C_NFORCE2) += i2c-nforce2.o
obj-$(CONFIG_I2C_NFORCE2_S4985) += i2c-nforce2-s4985.o
+obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o
obj-$(CONFIG_I2C_PIIX4) += i2c-piix4.o
obj-$(CONFIG_I2C_SIS5595) += i2c-sis5595.o
obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o
diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-gpu.c
new file mode 100644
index 000000000000..8822357bca0c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-nvidia-gpu.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nvidia GPU I2C controller Driver
+ *
+ * Copyright (C) 2018 NVIDIA Corporation. All rights reserved.
+ * Author: Ajay Gupta <ajayg@nvidia.com>
+ */
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+
+#include <asm/unaligned.h>
+
+/* I2C definitions */
+#define I2C_MST_CNTL 0x00
+#define I2C_MST_CNTL_GEN_START BIT(0)
+#define I2C_MST_CNTL_GEN_STOP BIT(1)
+#define I2C_MST_CNTL_CMD_READ (1 << 2)
+#define I2C_MST_CNTL_CMD_WRITE (2 << 2)
+#define I2C_MST_CNTL_BURST_SIZE_SHIFT 6
+#define I2C_MST_CNTL_GEN_NACK BIT(28)
+#define I2C_MST_CNTL_STATUS GENMASK(30, 29)
+#define I2C_MST_CNTL_STATUS_OKAY (0 << 29)
+#define I2C_MST_CNTL_STATUS_NO_ACK (1 << 29)
+#define I2C_MST_CNTL_STATUS_TIMEOUT (2 << 29)
+#define I2C_MST_CNTL_STATUS_BUS_BUSY (3 << 29)
+#define I2C_MST_CNTL_CYCLE_TRIGGER BIT(31)
+
+#define I2C_MST_ADDR 0x04
+
+#define I2C_MST_I2C0_TIMING 0x08
+#define I2C_MST_I2C0_TIMING_SCL_PERIOD_100KHZ 0x10e
+#define I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT 16
+#define I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT_MAX 255
+#define I2C_MST_I2C0_TIMING_TIMEOUT_CHECK BIT(24)
+
+#define I2C_MST_DATA 0x0c
+
+#define I2C_MST_HYBRID_PADCTL 0x20
+#define I2C_MST_HYBRID_PADCTL_MODE_I2C BIT(0)
+#define I2C_MST_HYBRID_PADCTL_I2C_SCL_INPUT_RCV BIT(14)
+#define I2C_MST_HYBRID_PADCTL_I2C_SDA_INPUT_RCV BIT(15)
+
+struct gpu_i2c_dev {
+ struct device *dev;
+ void __iomem *regs;
+ struct i2c_adapter adapter;
+ struct i2c_board_info *gpu_ccgx_ucsi;
+};
+
+static void gpu_enable_i2c_bus(struct gpu_i2c_dev *i2cd)
+{
+ u32 val;
+
+ /* enable I2C */
+ val = readl(i2cd->regs + I2C_MST_HYBRID_PADCTL);
+ val |= I2C_MST_HYBRID_PADCTL_MODE_I2C |
+ I2C_MST_HYBRID_PADCTL_I2C_SCL_INPUT_RCV |
+ I2C_MST_HYBRID_PADCTL_I2C_SDA_INPUT_RCV;
+ writel(val, i2cd->regs + I2C_MST_HYBRID_PADCTL);
+
+ /* enable 100KHZ mode */
+ val = I2C_MST_I2C0_TIMING_SCL_PERIOD_100KHZ;
+ val |= (I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT_MAX
+ << I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT);
+ val |= I2C_MST_I2C0_TIMING_TIMEOUT_CHECK;
+ writel(val, i2cd->regs + I2C_MST_I2C0_TIMING);
+}
+
+static int gpu_i2c_check_status(struct gpu_i2c_dev *i2cd)
+{
+ unsigned long target = jiffies + msecs_to_jiffies(1000);
+ u32 val;
+
+ do {
+ val = readl(i2cd->regs + I2C_MST_CNTL);
+ if (!(val & I2C_MST_CNTL_CYCLE_TRIGGER))
+ break;
+ if ((val & I2C_MST_CNTL_STATUS) !=
+ I2C_MST_CNTL_STATUS_BUS_BUSY)
+ break;
+ usleep_range(500, 600);
+ } while (time_is_after_jiffies(target));
+
+ if (time_is_before_jiffies(target)) {
+ dev_err(i2cd->dev, "i2c timeout error %x\n", val);
+ return -ETIME;
+ }
+
+ val = readl(i2cd->regs + I2C_MST_CNTL);
+ switch (val & I2C_MST_CNTL_STATUS) {
+ case I2C_MST_CNTL_STATUS_OKAY:
+ return 0;
+ case I2C_MST_CNTL_STATUS_NO_ACK:
+ return -EIO;
+ case I2C_MST_CNTL_STATUS_TIMEOUT:
+ return -ETIME;
+ default:
+ return 0;
+ }
+}
+
+static int gpu_i2c_read(struct gpu_i2c_dev *i2cd, u8 *data, u16 len)
+{
+ int status;
+ u32 val;
+
+ val = I2C_MST_CNTL_GEN_START | I2C_MST_CNTL_CMD_READ |
+ (len << I2C_MST_CNTL_BURST_SIZE_SHIFT) |
+ I2C_MST_CNTL_CYCLE_TRIGGER | I2C_MST_CNTL_GEN_NACK;
+ writel(val, i2cd->regs + I2C_MST_CNTL);
+
+ status = gpu_i2c_check_status(i2cd);
+ if (status < 0)
+ return status;
+
+ val = readl(i2cd->regs + I2C_MST_DATA);
+ switch (len) {
+ case 1:
+ data[0] = val;
+ break;
+ case 2:
+ put_unaligned_be16(val, data);
+ break;
+ case 3:
+ put_unaligned_be16(val >> 8, data);
+ data[2] = val;
+ break;
+ case 4:
+ put_unaligned_be32(val, data);
+ break;
+ default:
+ break;
+ }
+ return status;
+}
+
+static int gpu_i2c_start(struct gpu_i2c_dev *i2cd)
+{
+ writel(I2C_MST_CNTL_GEN_START, i2cd->regs + I2C_MST_CNTL);
+ return gpu_i2c_check_status(i2cd);
+}
+
+static int gpu_i2c_stop(struct gpu_i2c_dev *i2cd)
+{
+ writel(I2C_MST_CNTL_GEN_STOP, i2cd->regs + I2C_MST_CNTL);
+ return gpu_i2c_check_status(i2cd);
+}
+
+static int gpu_i2c_write(struct gpu_i2c_dev *i2cd, u8 data)
+{
+ u32 val;
+
+ writel(data, i2cd->regs + I2C_MST_DATA);
+
+ val = I2C_MST_CNTL_CMD_WRITE | (1 << I2C_MST_CNTL_BURST_SIZE_SHIFT);
+ writel(val, i2cd->regs + I2C_MST_CNTL);
+
+ return gpu_i2c_check_status(i2cd);
+}
+
+static int gpu_i2c_master_xfer(struct i2c_adapter *adap,
+ struct i2c_msg *msgs, int num)
+{
+ struct gpu_i2c_dev *i2cd = i2c_get_adapdata(adap);
+ int status, status2;
+ int i, j;
+
+ /*
+ * The controller supports maximum 4 byte read due to known
+ * limitation of sending STOP after every read.
+ */
+ for (i = 0; i < num; i++) {
+ if (msgs[i].flags & I2C_M_RD) {
+ /* program client address before starting read */
+ writel(msgs[i].addr, i2cd->regs + I2C_MST_ADDR);
+ /* gpu_i2c_read has implicit start */
+ status = gpu_i2c_read(i2cd, msgs[i].buf, msgs[i].len);
+ if (status < 0)
+ goto stop;
+ } else {
+ u8 addr = i2c_8bit_addr_from_msg(msgs + i);
+
+ status = gpu_i2c_start(i2cd);
+ if (status < 0) {
+ if (i == 0)
+ return status;
+ goto stop;
+ }
+
+ status = gpu_i2c_write(i2cd, addr);
+ if (status < 0)
+ goto stop;
+
+ for (j = 0; j < msgs[i].len; j++) {
+ status = gpu_i2c_write(i2cd, msgs[i].buf[j]);
+ if (status < 0)
+ goto stop;
+ }
+ }
+ }
+ status = gpu_i2c_stop(i2cd);
+ if (status < 0)
+ return status;
+
+ return i;
+stop:
+ status2 = gpu_i2c_stop(i2cd);
+ if (status2 < 0)
+ dev_err(i2cd->dev, "i2c stop failed %d\n", status2);
+ return status;
+}
+
+static const struct i2c_adapter_quirks gpu_i2c_quirks = {
+ .max_read_len = 4,
+ .flags = I2C_AQ_COMB_WRITE_THEN_READ,
+};
+
+static u32 gpu_i2c_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm gpu_i2c_algorithm = {
+ .master_xfer = gpu_i2c_master_xfer,
+ .functionality = gpu_i2c_functionality,
+};
+
+/*
+ * This driver is for Nvidia GPU cards with USB Type-C interface.
+ * We want to identify the cards using vendor ID and class code only
+ * to avoid dependency of adding product id for any new card which
+ * requires this driver.
+ * Currently there is no class code defined for UCSI device over PCI
+ * so using UNKNOWN class for now and it will be updated when UCSI
+ * over PCI gets a class code.
+ * There is no other NVIDIA cards with UNKNOWN class code. Even if the
+ * driver gets loaded for an undesired card then eventually i2c_read()
+ * (initiated from UCSI i2c_client) will timeout or UCSI commands will
+ * timeout.
+ */
+#define PCI_CLASS_SERIAL_UNKNOWN 0x0c80
+static const struct pci_device_id gpu_i2c_ids[] = {
+ { PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
+ PCI_CLASS_SERIAL_UNKNOWN << 8, 0xffffff00},
+ { }
+};
+MODULE_DEVICE_TABLE(pci, gpu_i2c_ids);
+
+static int gpu_populate_client(struct gpu_i2c_dev *i2cd, int irq)
+{
+ struct i2c_client *ccgx_client;
+
+ i2cd->gpu_ccgx_ucsi = devm_kzalloc(i2cd->dev,
+ sizeof(*i2cd->gpu_ccgx_ucsi),
+ GFP_KERNEL);
+ if (!i2cd->gpu_ccgx_ucsi)
+ return -ENOMEM;
+
+ strlcpy(i2cd->gpu_ccgx_ucsi->type, "ccgx-ucsi",
+ sizeof(i2cd->gpu_ccgx_ucsi->type));
+ i2cd->gpu_ccgx_ucsi->addr = 0x8;
+ i2cd->gpu_ccgx_ucsi->irq = irq;
+ ccgx_client = i2c_new_device(&i2cd->adapter, i2cd->gpu_ccgx_ucsi);
+ if (!ccgx_client)
+ return -ENODEV;
+
+ return 0;
+}
+
+static int gpu_i2c_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct gpu_i2c_dev *i2cd;
+ int status;
+
+ i2cd = devm_kzalloc(&pdev->dev, sizeof(*i2cd), GFP_KERNEL);
+ if (!i2cd)
+ return -ENOMEM;
+
+ i2cd->dev = &pdev->dev;
+ dev_set_drvdata(&pdev->dev, i2cd);
+
+ status = pcim_enable_device(pdev);
+ if (status < 0) {
+ dev_err(&pdev->dev, "pcim_enable_device failed %d\n", status);
+ return status;
+ }
+
+ pci_set_master(pdev);
+
+ i2cd->regs = pcim_iomap(pdev, 0, 0);
+ if (!i2cd->regs) {
+ dev_err(&pdev->dev, "pcim_iomap failed\n");
+ return -ENOMEM;
+ }
+
+ status = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
+ if (status < 0) {
+ dev_err(&pdev->dev, "pci_alloc_irq_vectors err %d\n", status);
+ return status;
+ }
+
+ gpu_enable_i2c_bus(i2cd);
+
+ i2c_set_adapdata(&i2cd->adapter, i2cd);
+ i2cd->adapter.owner = THIS_MODULE;
+ strlcpy(i2cd->adapter.name, "NVIDIA GPU I2C adapter",
+ sizeof(i2cd->adapter.name));
+ i2cd->adapter.algo = &gpu_i2c_algorithm;
+ i2cd->adapter.quirks = &gpu_i2c_quirks;
+ i2cd->adapter.dev.parent = &pdev->dev;
+ status = i2c_add_adapter(&i2cd->adapter);
+ if (status < 0)
+ goto free_irq_vectors;
+
+ status = gpu_populate_client(i2cd, pdev->irq);
+ if (status < 0) {
+ dev_err(&pdev->dev, "gpu_populate_client failed %d\n", status);
+ goto del_adapter;
+ }
+
+ return 0;
+
+del_adapter:
+ i2c_del_adapter(&i2cd->adapter);
+free_irq_vectors:
+ pci_free_irq_vectors(pdev);
+ return status;
+}
+
+static void gpu_i2c_remove(struct pci_dev *pdev)
+{
+ struct gpu_i2c_dev *i2cd = dev_get_drvdata(&pdev->dev);
+
+ i2c_del_adapter(&i2cd->adapter);
+ pci_free_irq_vectors(pdev);
+}
+
+static int gpu_i2c_resume(struct device *dev)
+{
+ struct gpu_i2c_dev *i2cd = dev_get_drvdata(dev);
+
+ gpu_enable_i2c_bus(i2cd);
+ return 0;
+}
+
+static UNIVERSAL_DEV_PM_OPS(gpu_i2c_driver_pm, NULL, gpu_i2c_resume, NULL);
+
+static struct pci_driver gpu_i2c_driver = {
+ .name = "nvidia-gpu",
+ .id_table = gpu_i2c_ids,
+ .probe = gpu_i2c_probe,
+ .remove = gpu_i2c_remove,
+ .driver = {
+ .pm = &gpu_i2c_driver_pm,
+ },
+};
+
+module_pci_driver(gpu_i2c_driver);
+
+MODULE_AUTHOR("Ajay Gupta <ajayg@nvidia.com>");
+MODULE_DESCRIPTION("Nvidia GPU I2C controller Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index 527f55c8c4c7..db075bc0d952 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -571,18 +571,19 @@ static int geni_i2c_probe(struct platform_device *pdev)
dev_dbg(&pdev->dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
- ret = i2c_add_adapter(&gi2c->adap);
- if (ret) {
- dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
- return ret;
- }
-
gi2c->suspended = 1;
pm_runtime_set_suspended(gi2c->se.dev);
pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY);
pm_runtime_use_autosuspend(gi2c->se.dev);
pm_runtime_enable(gi2c->se.dev);
+ ret = i2c_add_adapter(&gi2c->adap);
+ if (ret) {
+ dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
+ pm_runtime_disable(gi2c->se.dev);
+ return ret;
+ }
+
return 0;
}
@@ -590,8 +591,8 @@ static int geni_i2c_remove(struct platform_device *pdev)
{
struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
- pm_runtime_disable(gi2c->se.dev);
i2c_del_adapter(&gi2c->adap);
+ pm_runtime_disable(gi2c->se.dev);
return 0;
}
diff --git a/drivers/usb/typec/ucsi/Kconfig b/drivers/usb/typec/ucsi/Kconfig
index e36d6c73c4a4..78118883f96c 100644
--- a/drivers/usb/typec/ucsi/Kconfig
+++ b/drivers/usb/typec/ucsi/Kconfig
@@ -23,6 +23,16 @@ config TYPEC_UCSI
if TYPEC_UCSI
+config UCSI_CCG
+ tristate "UCSI Interface Driver for Cypress CCGx"
+ depends on I2C
+ help
+ This driver enables UCSI support on platforms that expose a
+ Cypress CCGx Type-C controller over I2C interface.
+
+ To compile the driver as a module, choose M here: the module will be
+ called ucsi_ccg.
+
config UCSI_ACPI
tristate "UCSI ACPI Interface Driver"
depends on ACPI
diff --git a/drivers/usb/typec/ucsi/Makefile b/drivers/usb/typec/ucsi/Makefile
index 7afbea512207..2f4900b26210 100644
--- a/drivers/usb/typec/ucsi/Makefile
+++ b/drivers/usb/typec/ucsi/Makefile
@@ -8,3 +8,5 @@ typec_ucsi-y := ucsi.o
typec_ucsi-$(CONFIG_TRACING) += trace.o
obj-$(CONFIG_UCSI_ACPI) += ucsi_acpi.o
+
+obj-$(CONFIG_UCSI_CCG) += ucsi_ccg.o
diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
new file mode 100644
index 000000000000..de8a43bdff68
--- /dev/null
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -0,0 +1,307 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * UCSI driver for Cypress CCGx Type-C controller
+ *
+ * Copyright (C) 2017-2018 NVIDIA Corporation. All rights reserved.
+ * Author: Ajay Gupta <ajayg@nvidia.com>
+ *
+ * Some code borrowed from drivers/usb/typec/ucsi/ucsi_acpi.c
+ */
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#include <asm/unaligned.h>
+#include "ucsi.h"
+
+struct ucsi_ccg {
+ struct device *dev;
+ struct ucsi *ucsi;
+ struct ucsi_ppm ppm;
+ struct i2c_client *client;
+};
+
+#define CCGX_RAB_INTR_REG 0x06
+#define CCGX_RAB_UCSI_CONTROL 0x39
+#define CCGX_RAB_UCSI_CONTROL_START BIT(0)
+#define CCGX_RAB_UCSI_CONTROL_STOP BIT(1)
+#define CCGX_RAB_UCSI_DATA_BLOCK(offset) (0xf000 | ((offset) & 0xff))
+
+static int ccg_read(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len)
+{
+ struct i2c_client *client = uc->client;
+ const struct i2c_adapter_quirks *quirks = client->adapter->quirks;
+ unsigned char buf[2];
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .flags = 0x0,
+ .len = sizeof(buf),
+ .buf = buf,
+ },
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .buf = data,
+ },
+ };
+ u32 rlen, rem_len = len, max_read_len = len;
+ int status;
+
+ /* check any max_read_len limitation on i2c adapter */
+ if (quirks && quirks->max_read_len)
+ max_read_len = quirks->max_read_len;
+
+ while (rem_len > 0) {
+ msgs[1].buf = &data[len - rem_len];
+ rlen = min_t(u16, rem_len, max_read_len);
+ msgs[1].len = rlen;
+ put_unaligned_le16(rab, buf);
+ status = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (status < 0) {
+ dev_err(uc->dev, "i2c_transfer failed %d\n", status);
+ return status;
+ }
+ rab += rlen;
+ rem_len -= rlen;
+ }
+
+ return 0;
+}
+
+static int ccg_write(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len)
+{
+ struct i2c_client *client = uc->client;
+ unsigned char *buf;
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .flags = 0x0,
+ }
+ };
+ int status;
+
+ buf = kzalloc(len + sizeof(rab), GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ put_unaligned_le16(rab, buf);
+ memcpy(buf + sizeof(rab), data, len);
+
+ msgs[0].len = len + sizeof(rab);
+ msgs[0].buf = buf;
+
+ status = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (status < 0) {
+ dev_err(uc->dev, "i2c_transfer failed %d\n", status);
+ kfree(buf);
+ return status;
+ }
+
+ kfree(buf);
+ return 0;
+}
+
+static int ucsi_ccg_init(struct ucsi_ccg *uc)
+{
+ unsigned int count = 10;
+ u8 data;
+ int status;
+
+ data = CCGX_RAB_UCSI_CONTROL_STOP;
+ status = ccg_write(uc, CCGX_RAB_UCSI_CONTROL, &data, sizeof(data));
+ if (status < 0)
+ return status;
+
+ data = CCGX_RAB_UCSI_CONTROL_START;
+ status = ccg_write(uc, CCGX_RAB_UCSI_CONTROL, &data, sizeof(data));
+ if (status < 0)
+ return status;
+
+ /*
+ * Flush CCGx RESPONSE queue by acking interrupts. Above ucsi control
+ * register write will push response which must be cleared.
+ */
+ do {
+ status = ccg_read(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
+ if (status < 0)
+ return status;
+
+ if (!data)
+ return 0;
+
+ status = ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
+ if (status < 0)
+ return status;
+
+ usleep_range(10000, 11000);
+ } while (--count);
+
+ return -ETIMEDOUT;
+}
+
+static int ucsi_ccg_send_data(struct ucsi_ccg *uc)
+{
+ u8 *ppm = (u8 *)uc->ppm.data;
+ int status;
+ u16 rab;
+
+ rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, message_out));
+ status = ccg_write(uc, rab, ppm +
+ offsetof(struct ucsi_data, message_out),
+ sizeof(uc->ppm.data->message_out));
+ if (status < 0)
+ return status;
+
+ rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, ctrl));
+ return ccg_write(uc, rab, ppm + offsetof(struct ucsi_data, ctrl),
+ sizeof(uc->ppm.data->ctrl));
+}
+
+static int ucsi_ccg_recv_data(struct ucsi_ccg *uc)
+{
+ u8 *ppm = (u8 *)uc->ppm.data;
+ int status;
+ u16 rab;
+
+ rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, cci));
+ status = ccg_read(uc, rab, ppm + offsetof(struct ucsi_data, cci),
+ sizeof(uc->ppm.data->cci));
+ if (status < 0)
+ return status;
+
+ rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, message_in));
+ return ccg_read(uc, rab, ppm + offsetof(struct ucsi_data, message_in),
+ sizeof(uc->ppm.data->message_in));
+}
+
+static int ucsi_ccg_ack_interrupt(struct ucsi_ccg *uc)
+{
+ int status;
+ unsigned char data;
+
+ status = ccg_read(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
+ if (status < 0)
+ return status;
+
+ return ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
+}
+
+static int ucsi_ccg_sync(struct ucsi_ppm *ppm)
+{
+ struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm);
+ int status;
+
+ status = ucsi_ccg_recv_data(uc);
+ if (status < 0)
+ return status;
+
+ /* ack interrupt to allow next command to run */
+ return ucsi_ccg_ack_interrupt(uc);
+}
+
+static int ucsi_ccg_cmd(struct ucsi_ppm *ppm, struct ucsi_control *ctrl)
+{
+ struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm);
+
+ ppm->data->ctrl.raw_cmd = ctrl->raw_cmd;
+ return ucsi_ccg_send_data(uc);
+}
+
+static irqreturn_t ccg_irq_handler(int irq, void *data)
+{
+ struct ucsi_ccg *uc = data;
+
+ ucsi_notify(uc->ucsi);
+
+ return IRQ_HANDLED;
+}
+
+static int ucsi_ccg_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct ucsi_ccg *uc;
+ int status;
+ u16 rab;
+
+ uc = devm_kzalloc(dev, sizeof(*uc), GFP_KERNEL);
+ if (!uc)
+ return -ENOMEM;
+
+ uc->ppm.data = devm_kzalloc(dev, sizeof(struct ucsi_data), GFP_KERNEL);
+ if (!uc->ppm.data)
+ return -ENOMEM;
+
+ uc->ppm.cmd = ucsi_ccg_cmd;
+ uc->ppm.sync = ucsi_ccg_sync;
+ uc->dev = dev;
+ uc->client = client;
+
+ /* reset ccg device and initialize ucsi */
+ status = ucsi_ccg_init(uc);
+ if (status < 0) {
+ dev_err(uc->dev, "ucsi_ccg_init failed - %d\n", status);
+ return status;
+ }
+
+ status = devm_request_threaded_irq(dev, client->irq, NULL,
+ ccg_irq_handler,
+ IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
+ dev_name(dev), uc);
+ if (status < 0) {
+ dev_err(uc->dev, "request_threaded_irq failed - %d\n", status);
+ return status;
+ }
+
+ uc->ucsi = ucsi_register_ppm(dev, &uc->ppm);
+ if (IS_ERR(uc->ucsi)) {
+ dev_err(uc->dev, "ucsi_register_ppm failed\n");
+ return PTR_ERR(uc->ucsi);
+ }
+
+ rab = CCGX_RAB_UCSI_DATA_BLOCK(offsetof(struct ucsi_data, version));
+ status = ccg_read(uc, rab, (u8 *)(uc->ppm.data) +
+ offsetof(struct ucsi_data, version),
+ sizeof(uc->ppm.data->version));
+ if (status < 0) {
+ ucsi_unregister_ppm(uc->ucsi);
+ return status;
+ }
+
+ i2c_set_clientdata(client, uc);
+ return 0;
+}
+
+static int ucsi_ccg_remove(struct i2c_client *client)
+{
+ struct ucsi_ccg *uc = i2c_get_clientdata(client);
+
+ ucsi_unregister_ppm(uc->ucsi);
+
+ return 0;
+}
+
+static const struct i2c_device_id ucsi_ccg_device_id[] = {
+ {"ccgx-ucsi", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, ucsi_ccg_device_id);
+
+static struct i2c_driver ucsi_ccg_driver = {
+ .driver = {
+ .name = "ucsi_ccg",
+ },
+ .probe = ucsi_ccg_probe,
+ .remove = ucsi_ccg_remove,
+ .id_table = ucsi_ccg_device_id,
+};
+
+module_i2c_driver(ucsi_ccg_driver);
+
+MODULE_AUTHOR("Ajay Gupta <ajayg@nvidia.com>");
+MODULE_DESCRIPTION("UCSI driver for Cypress CCGx Type-C controller");
+MODULE_LICENSE("GPL v2");