Add Zhaoxin I2C controller driver. It provides the access to the i2c busses, which connects to the touchpad, eeprom, etc. Zhaoxin I2C controller provides two modes of operation: FIFO mode: works in access requests without restart. Byte mode: same IP with i2c-wmt and use driver i2c-viai2c-common. Zhaoxin I2C controller has two separate busses, so may accommodate up to two I2C adapters. Those adapters are listed in the ACPI namespace with the "IIC1D17" HID, and probed by a platform driver. The driver works with IRQ mode, and supports basic I2C features. Flags I2C_AQ_NO_ZERO_LEN and I2C_AQ_COMB_WRITE_THEN_READ are used to limit the unsupported access. Signed-off-by: Hans Hu <hanshu-oc@xxxxxxxxxxx> --- MAINTAINERS | 7 + drivers/i2c/busses/Kconfig | 11 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-viai2c-common.c | 12 +- drivers/i2c/busses/i2c-viai2c-common.h | 11 + drivers/i2c/busses/i2c-wmt.c | 2 + drivers/i2c/busses/i2c-zhaoxin.c | 274 +++++++++++++++++++++++++ 7 files changed, 315 insertions(+), 3 deletions(-) create mode 100644 drivers/i2c/busses/i2c-zhaoxin.c diff --git a/MAINTAINERS b/MAINTAINERS index b3648da1c5b2..bb65f7d748eb 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9864,6 +9864,13 @@ L: linux-i2c@xxxxxxxxxxxxxxx F: Documentation/i2c/busses/i2c-ismt.rst F: drivers/i2c/busses/i2c-ismt.c +I2C/SMBUS ZHAOXIN DRIVER +M: Hans Hu <hanshu@xxxxxxxxxxx> +L: linux-i2c@xxxxxxxxxxxxxxx +S: Maintained +W: https://www.zhaoxin.com +F: drivers/i2c/busses/i2c-zhaoxin.c + I2C/SMBUS STUB DRIVER M: Jean Delvare <jdelvare@xxxxxxxx> L: linux-i2c@xxxxxxxxxxxxxxx diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index b810030b21cd..4941093299b2 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -347,6 +347,17 @@ config I2C_SCMI To compile this driver as a module, choose M here: the module will be called i2c-scmi. +config I2C_ZHAOXIN + tristate "Zhaoxin I2C Interface" + depends on PCI || COMPILE_TEST + select I2C_VIAI2C_COMMON + help + If you say yes to this option, support will be included for the + ZHAOXIN I2C interface + + This driver can also be built as a module. If so, the module + will be called i2c-zhaoxin. + endif # ACPI comment "Mac SMBus host controller drivers" diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index b7e20c3531b5..47bfab15b0a1 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o obj-$(CONFIG_I2C_VIA) += i2c-via.o obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o +obj-$(CONFIG_I2C_ZHAOXIN) += i2c-zhaoxin.o # Mac SMBus host controller drivers obj-$(CONFIG_I2C_HYDRA) += i2c-hydra.o diff --git a/drivers/i2c/busses/i2c-viai2c-common.c b/drivers/i2c/busses/i2c-viai2c-common.c index ffba29ce17c5..9d400ab10c25 100644 --- a/drivers/i2c/busses/i2c-viai2c-common.c +++ b/drivers/i2c/busses/i2c-viai2c-common.c @@ -53,7 +53,8 @@ static int via_i2c_write(struct via_i2c *i2c, struct i2c_msg *pmsg, int last) writew(pmsg->buf[0], base + VIAI2C_CDR); } - if (!(pmsg->flags & I2C_M_NOSTART)) { + if (!(pmsg->flags & I2C_M_NOSTART) + && (i2c->platform & VIAI2C_PLAT_WMT)) { val = readb(base + VIAI2C_CR); val &= ~VIAI2C_CR_TX_END; val |= VIAI2C_CR_CPU_RDY; @@ -94,8 +95,10 @@ static int via_i2c_write(struct via_i2c *i2c, struct i2c_msg *pmsg, int last) } if (xfer_len == pmsg->len) { - if (last != 1) + if (last != 1 && (i2c->platform & VIAI2C_PLAT_WMT)) writeb(VIAI2C_CR_ENABLE, base + VIAI2C_CR); + else if (last && (i2c->platform & VIAI2C_PLAT_ZHAOXIN)) + writeb(VIAI2C_CR_TX_END, base + VIAI2C_CR); } else { writeb(pmsg->buf[xfer_len] & 0xFF, base + VIAI2C_CDR); writeb(VIAI2C_CR_CONTINUE_MASK, base + VIAI2C_CR); @@ -159,7 +162,8 @@ int via_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) for (i = 0; ret >= 0 && i < num; i++) { struct i2c_msg * pmsg = &msgs[i]; - if (!(pmsg->flags & I2C_M_NOSTART)) { + if (!(pmsg->flags & I2C_M_NOSTART) + && (i2c->platform & VIAI2C_PLAT_WMT)) { ret = via_i2c_wait_bus_ready(i2c); if (ret < 0) return ret; @@ -181,6 +185,8 @@ static irqreturn_t via_i2c_isr(int irq, void *data) /* save the status and write-clear it */ i2c->event = readw(i2c->base + VIAI2C_ISR); + if (!i2c->event) + return IRQ_NONE; writew(i2c->event, i2c->base + VIAI2C_ISR); complete(&i2c->complete); diff --git a/drivers/i2c/busses/i2c-viai2c-common.h b/drivers/i2c/busses/i2c-viai2c-common.h index f3a86f005eb9..c81018b440b2 100644 --- a/drivers/i2c/busses/i2c-viai2c-common.h +++ b/drivers/i2c/busses/i2c-viai2c-common.h @@ -46,6 +46,11 @@ #define VIAI2C_TIMEOUT (msecs_to_jiffies(1000)) +enum { + VIAI2C_PLAT_WMT, + VIAI2C_PLAT_ZHAOXIN +}; + struct via_i2c { struct i2c_adapter adapter; struct completion complete; @@ -55,6 +60,12 @@ struct via_i2c { int irq; u16 event; u16 tcr; + bool platform; + u16 tr; + u16 mcr; + u16 csr; + u8 fstp; + u8 hrv; }; int via_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num); diff --git a/drivers/i2c/busses/i2c-wmt.c b/drivers/i2c/busses/i2c-wmt.c index d282f2146fb3..c9c3d27e8331 100644 --- a/drivers/i2c/busses/i2c-wmt.c +++ b/drivers/i2c/busses/i2c-wmt.c @@ -78,6 +78,8 @@ static int wmt_i2c_probe(struct platform_device *pdev) if (err) return err; + i2c_dev->platform = VIAI2C_PLAT_WMT; + i2c_dev->clk = of_clk_get(np, 0); if (IS_ERR(i2c_dev->clk)) return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk), diff --git a/drivers/i2c/busses/i2c-zhaoxin.c b/drivers/i2c/busses/i2c-zhaoxin.c new file mode 100644 index 000000000000..73b10af9a7b9 --- /dev/null +++ b/drivers/i2c/busses/i2c-zhaoxin.c @@ -0,0 +1,274 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright(c) 2023 Shanghai Zhaoxin Semiconductor Corporation. + * All rights reserved. + */ + +#include <linux/pci.h> +#include "i2c-viai2c-common.h" + +#define ZXI2C_NAME "Zhaoxin-I2C" + +/* + * zhaoxin custom registers and bits + */ +/* reg CR Bit fields */ +#define ZXI2C_CR_FIFO_EN BIT(14) +/* reg ISR Bit fields */ +#define ZXI2C_ISR_FIFO BIT(3) +/* reg IMR Bit fields */ +#define ZXI2C_IMR_FIFO BIT(3) +#define ZXI2C_IMR_FIFO_MASK (BIT(3) | VIAI2C_IMR_ADDRNACK) +#define ZXI2C_IMR_BYTE_MASK (BIT(1) | VIAI2C_IMR_ADDRNACK) +#define ZXI2C_CS 0x10 +#define ZXI2C_CS_CLK_50M BIT(0) +#define ZXI2C_REV 0x11 +#define ZXI2C_HCR 0x12 +#define ZXI2C_HCR_FIFO_RST GENMASK(1, 0) +#define ZXI2C_HTDR 0x13 +#define ZXI2C_HRDR 0x14 +#define ZXI2C_HTLR 0x15 +#define ZXI2C_HRLR 0x16 +#define ZXI2C_HWCNTR 0x18 +#define ZXI2C_HRCNTR 0x19 + +/* parameters Constants */ +#define ZXI2C_GOLD_FSTP_100K 0xF3 +#define ZXI2C_GOLD_FSTP_400K 0x38 +#define ZXI2C_GOLD_FSTP_1M 0x13 +#define ZXI2C_GOLD_FSTP_3400K 0x37 +#define ZXI2C_HS_MASTER_CODE (0x08 << 8) + +#define ZXI2C_FIFO_SIZE 32 + +#define zxi2c via_i2c + +static int zxi2c_fifo_xfer(struct zxi2c *i2c, struct i2c_msg *msg) +{ + int err; + u16 i, finished; + u16 tcr_val = i2c->tcr; + void __iomem *base = i2c->base; + int read = !!(msg->flags & I2C_M_RD); + + /* reset fifo settings */ + iowrite8(ZXI2C_HCR_FIFO_RST, base + ZXI2C_HCR); + /* select fifo mode */ + iowrite16(ZXI2C_CR_FIFO_EN, i2c->base + VIAI2C_CR); + /* enable fifo interrupt */ + iowrite8(ZXI2C_IMR_FIFO_MASK, base + VIAI2C_IMR); + + /* sets the transmission length, direction, and the data to be sent */ + if (read) { + tcr_val |= VIAI2C_TCR_READ; + iowrite8(msg->len - 1, base + ZXI2C_HRLR); + } else { + + iowrite8(msg->len - 1, base + ZXI2C_HTLR); + for (i = 0; i < msg->len; i++) + iowrite8(msg->buf[i], base + ZXI2C_HTDR); + } + /* set slave addr */ + tcr_val |= (msg->addr & VIAI2C_TCR_ADDR_MASK); + + reinit_completion(&i2c->complete); + + /* a write to the TCR triggers the transfer start */ + iowrite16(tcr_val, i2c->base + VIAI2C_TCR); + + err = via_i2c_wait_event(i2c, ZXI2C_ISR_FIFO); + if (err) + return err; + + /* Gets the length and data that has been transferred */ + if (read) { + finished = ioread8(base + ZXI2C_HRCNTR); + for (i = 0; i < finished; i++) + msg->buf[i] = ioread8(base + ZXI2C_HRDR); + } else { + finished = ioread8(base + ZXI2C_HWCNTR); + } + + /* check if data NACK during transmitting */ + if (finished != msg->len) { + dev_err(i2c->dev, "only %s %d/%d bytes\n", + read ? "read" : "write", finished, msg->len); + return -EAGAIN; + } + + return 1; +} + +static int zxi2c_byte_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + int err; + struct zxi2c *i2c = (struct zxi2c *)i2c_get_adapdata(adap); + + /* select byte mode */ + iowrite16(0, i2c->base + VIAI2C_CR); + /* enable interrupt */ + iowrite8(ZXI2C_IMR_BYTE_MASK, i2c->base + VIAI2C_IMR); + + err = via_i2c_xfer(adap, msgs, num); + /* kill unfinished transfer signal */ + if (err < 0) + iowrite16(VIAI2C_CR_END_MASK, i2c->base + VIAI2C_CR); + + return err; +} + +static int zxi2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + int err; + struct zxi2c *i2c = (struct zxi2c *)i2c_get_adapdata(adap); + + err = via_i2c_wait_bus_ready(i2c); + if (err) + return err; + + if (num == 1 && msgs->len <= ZXI2C_FIFO_SIZE && msgs->len >= 2) + err = zxi2c_fifo_xfer(i2c, msgs); + else + err = zxi2c_byte_xfer(adap, msgs, num); + /* + * fifo or byte interrupts have been enabled inside the xfer functions. + * To make the code more concise, we put the disable action here + */ + iowrite8(0, i2c->base + VIAI2C_IMR); + return err; +} + +static u32 zxi2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm zxi2c_algorithm = { + .master_xfer = zxi2c_master_xfer, + .functionality = zxi2c_func, +}; + +static const struct i2c_adapter_quirks zxi2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN | I2C_AQ_COMB_WRITE_THEN_READ, +}; + +static const u32 zxi2c_speed_params_table[][3] = { + /* speed, ZXI2C_TCR, ZXI2C_FSTP */ + { I2C_MAX_STANDARD_MODE_FREQ, 0, ZXI2C_GOLD_FSTP_100K }, + { I2C_MAX_FAST_MODE_FREQ, VIAI2C_TCR_FAST, ZXI2C_GOLD_FSTP_400K }, + { I2C_MAX_FAST_MODE_PLUS_FREQ, VIAI2C_TCR_FAST, ZXI2C_GOLD_FSTP_1M }, + { I2C_MAX_HIGH_SPEED_MODE_FREQ, VIAI2C_TCR_HS_MODE | VIAI2C_TCR_FAST, + ZXI2C_GOLD_FSTP_3400K }, +}; + +static void zxi2c_set_bus_speed(struct zxi2c *i2c) +{ + iowrite16(i2c->tr, i2c->base + VIAI2C_TR); + iowrite8(ZXI2C_CS_CLK_50M, i2c->base + ZXI2C_CS); + iowrite16(i2c->mcr, i2c->base + VIAI2C_MCR); +} + +static void zxi2c_get_bus_speed(struct zxi2c *i2c) +{ + u8 i, count; + u8 fstp; + const u32 *params; + u32 acpi_speed = i2c_acpi_find_bus_speed(i2c->dev); + + count = ARRAY_SIZE(zxi2c_speed_params_table); + for (i = 0; i < count; i++) + if (acpi_speed == zxi2c_speed_params_table[i][0]) + break; + /* if not found, use 400k as default */ + i = i < count ? i : 1; + + params = zxi2c_speed_params_table[i]; + fstp = ioread8(i2c->base + VIAI2C_TR); + if (abs(fstp - params[2]) > 0x10) { + /* + * if BIOS setting value far from golden value, + * use golden value and warn user + */ + dev_warn(i2c->dev, "speed:%d, fstp:0x%x, golden:0x%x\n", + params[0], fstp, params[2]); + i2c->tr = params[2] | 0xff00; + } else { + i2c->tr = fstp | 0xff00; + } + + i2c->tcr = params[1]; + i2c->mcr = ioread16(i2c->base + VIAI2C_MCR); + /* for Hs-mode, use 0000 1000 as master code */ + if (params[0] == I2C_MAX_HIGH_SPEED_MODE_FREQ) + i2c->mcr |= ZXI2C_HS_MASTER_CODE; + + dev_info(i2c->dev, "speed mode is %s\n", + i2c_freq_mode_string(params[0])); +} + +static int zxi2c_probe(struct platform_device *pdev) +{ + int err = 0; + struct zxi2c *i2c; + struct pci_dev *pci; + + err = via_i2c_init(pdev, &i2c); + if (err) + return err; + + i2c->platform = VIAI2C_PLAT_ZHAOXIN; + i2c->hrv = ioread8(i2c->base + ZXI2C_REV); + i2c->csr = ioread16(i2c->base + VIAI2C_CSR); + + zxi2c_get_bus_speed(i2c); + zxi2c_set_bus_speed(i2c); + + i2c->adapter.owner = THIS_MODULE; + i2c->adapter.algo = &zxi2c_algorithm; + i2c->adapter.retries = 2; + i2c->adapter.quirks = &zxi2c_quirks; + i2c->adapter.dev.parent = &pdev->dev; + ACPI_COMPANION_SET(&i2c->adapter.dev, ACPI_COMPANION(&pdev->dev)); + pci = to_pci_dev(pdev->dev.parent); + snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), "%s-%s-%s", + ZXI2C_NAME, dev_name(&pci->dev), dev_name(i2c->dev)); + i2c_set_adapdata(&i2c->adapter, i2c); + + return devm_i2c_add_adapter(&pdev->dev, &i2c->adapter); +} + +static int zxi2c_resume(struct device *dev) +{ + struct zxi2c *i2c = dev_get_drvdata(dev); + + iowrite16(i2c->csr, i2c->base + VIAI2C_CSR); + zxi2c_set_bus_speed(i2c); + + return 0; +} + +static const struct dev_pm_ops zxi2c_pm = { + SET_SYSTEM_SLEEP_PM_OPS(NULL, zxi2c_resume) +}; + +static const struct acpi_device_id zxi2c_acpi_match[] = { + { "IIC1D17", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, zxi2c_acpi_match); + +static struct platform_driver zxi2c_driver = { + .probe = zxi2c_probe, + .driver = { + .name = ZXI2C_NAME, + .acpi_match_table = zxi2c_acpi_match, + .pm = &zxi2c_pm, + }, +}; +module_platform_driver(zxi2c_driver); + +MODULE_AUTHOR("HansHu@xxxxxxxxxxx"); +MODULE_DESCRIPTION("Shanghai Zhaoxin IIC driver"); +MODULE_LICENSE("GPL"); -- 2.34.1
