v6->v7: 1. adjust the patch sequence: move the split file patch to the front 2. rename i2c-wmt-plt.c to i2c-viai2c-wmt.c 3. remove '#define wmt_i2c viai2c', use viai2c directly Link: https://lore.kernel.org/all/1871ceb5c3d6804c6a7f7a38327919861985c066.1703830854.git.hanshu-oc@xxxxxxxxxxx/ Since the I2C IP of both wmt and zhaoxin originates from VIA, it is better to separate the common code first. The common driver is named as i2c-viai2c-common.c. Old i2c-wmt.c renamed to i2c-viai2c-wmt.c. The MAINTAINERS file will be updated accordingly in upcoming commits. Signed-off-by: Hans Hu <hanshu-oc@xxxxxxxxxxx> --- MAINTAINERS | 2 +- drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-viai2c-common.c | 221 +++++++++++++ drivers/i2c/busses/i2c-viai2c-common.h | 71 +++++ drivers/i2c/busses/i2c-viai2c-wmt.c | 143 +++++++++ drivers/i2c/busses/i2c-wmt.c | 422 ------------------------- 6 files changed, 437 insertions(+), 423 deletions(-) create mode 100644 drivers/i2c/busses/i2c-viai2c-common.c create mode 100644 drivers/i2c/busses/i2c-viai2c-common.h create mode 100644 drivers/i2c/busses/i2c-viai2c-wmt.c delete mode 100644 drivers/i2c/busses/i2c-wmt.c diff --git a/MAINTAINERS b/MAINTAINERS index 9104430e148e..a73ccc8e89d0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2988,7 +2988,7 @@ S: Orphan F: Documentation/devicetree/bindings/i2c/i2c-wmt.txt F: arch/arm/mach-vt8500/ F: drivers/clocksource/timer-vt8500.c -F: drivers/i2c/busses/i2c-wmt.c +F: drivers/i2c/busses/i2c-viai2c-wmt.c F: drivers/mmc/host/wmt-sdmmc.c F: drivers/pwm/pwm-vt8500.c F: drivers/rtc/rtc-vt8500.c diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 3757b9391e60..06ceb4775cbd 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -120,6 +120,7 @@ obj-$(CONFIG_I2C_TEGRA_BPMP) += i2c-tegra-bpmp.o obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o +i2c-wmt-objs := i2c-viai2c-wmt.o i2c-viai2c-common.o obj-$(CONFIG_I2C_WMT) += i2c-wmt.o i2c-octeon-objs := i2c-octeon-core.o i2c-octeon-platdrv.o obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o diff --git a/drivers/i2c/busses/i2c-viai2c-common.c b/drivers/i2c/busses/i2c-viai2c-common.c new file mode 100644 index 000000000000..fa47a4d9549c --- /dev/null +++ b/drivers/i2c/busses/i2c-viai2c-common.c @@ -0,0 +1,221 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include <linux/of_irq.h> +#include "i2c-viai2c-common.h" + +int wmt_i2c_wait_bus_not_busy(struct wmt_i2c_dev *i2c_dev) +{ + unsigned long timeout; + + timeout = jiffies + WMT_I2C_TIMEOUT; + while (!(readw(i2c_dev->base + REG_CSR) & CSR_READY_MASK)) { + if (time_after(jiffies, timeout)) { + dev_warn(i2c_dev->dev, "timeout waiting for bus ready\n"); + return -EBUSY; + } + msleep(20); + } + + return 0; +} + +int wmt_check_status(struct wmt_i2c_dev *i2c_dev) +{ + int ret = 0; + unsigned long wait_result; + + wait_result = wait_for_completion_timeout(&i2c_dev->complete, + msecs_to_jiffies(500)); + if (!wait_result) + return -ETIMEDOUT; + + if (i2c_dev->cmd_status & ISR_NACK_ADDR) + ret = -EIO; + + if (i2c_dev->cmd_status & ISR_SCL_TIMEOUT) + ret = -ETIMEDOUT; + + return ret; +} + +static int wmt_i2c_write(struct wmt_i2c_dev *i2c_dev, struct i2c_msg *pmsg, int last) +{ + u16 val, tcr_val = i2c_dev->tcr; + int ret; + int xfer_len = 0; + + if (pmsg->len == 0) { + /* + * We still need to run through the while (..) once, so + * start at -1 and break out early from the loop + */ + xfer_len = -1; + writew(0, i2c_dev->base + REG_CDR); + } else { + writew(pmsg->buf[0] & 0xFF, i2c_dev->base + REG_CDR); + } + + if (!(pmsg->flags & I2C_M_NOSTART)) { + val = readw(i2c_dev->base + REG_CR); + val &= ~CR_TX_END; + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + reinit_completion(&i2c_dev->complete); + + tcr_val |= (TCR_MASTER_WRITE | (pmsg->addr & TCR_SLAVE_ADDR_MASK)); + + writew(tcr_val, i2c_dev->base + REG_TCR); + + if (pmsg->flags & I2C_M_NOSTART) { + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + while (xfer_len < pmsg->len) { + ret = wmt_check_status(i2c_dev); + if (ret) + return ret; + + xfer_len++; + + val = readw(i2c_dev->base + REG_CSR); + if ((val & CSR_RCV_ACK_MASK) == CSR_RCV_NOT_ACK) { + dev_dbg(i2c_dev->dev, "write RCV NACK error\n"); + return -EIO; + } + + if (pmsg->len == 0) { + val = CR_TX_END | CR_CPU_RDY | CR_ENABLE; + writew(val, i2c_dev->base + REG_CR); + break; + } + + if (xfer_len == pmsg->len) { + if (last != 1) + writew(CR_ENABLE, i2c_dev->base + REG_CR); + } else { + writew(pmsg->buf[xfer_len] & 0xFF, i2c_dev->base + + REG_CDR); + writew(CR_CPU_RDY | CR_ENABLE, i2c_dev->base + REG_CR); + } + } + + return 0; +} + +static int wmt_i2c_read(struct wmt_i2c_dev *i2c_dev, struct i2c_msg *pmsg) +{ + u16 val, tcr_val = i2c_dev->tcr; + int ret; + u32 xfer_len = 0; + + val = readw(i2c_dev->base + REG_CR); + val &= ~(CR_TX_END | CR_TX_NEXT_NO_ACK); + + if (!(pmsg->flags & I2C_M_NOSTART)) + val |= CR_CPU_RDY; + + if (pmsg->len == 1) + val |= CR_TX_NEXT_NO_ACK; + + writew(val, i2c_dev->base + REG_CR); + + reinit_completion(&i2c_dev->complete); + + tcr_val |= TCR_MASTER_READ | (pmsg->addr & TCR_SLAVE_ADDR_MASK); + + writew(tcr_val, i2c_dev->base + REG_TCR); + + if (pmsg->flags & I2C_M_NOSTART) { + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + while (xfer_len < pmsg->len) { + ret = wmt_check_status(i2c_dev); + if (ret) + return ret; + + pmsg->buf[xfer_len] = readw(i2c_dev->base + REG_CDR) >> 8; + xfer_len++; + + val = readw(i2c_dev->base + REG_CR) | CR_CPU_RDY; + if (xfer_len == pmsg->len - 1) + val |= CR_TX_NEXT_NO_ACK; + writew(val, i2c_dev->base + REG_CR); + } + + return 0; +} + +int wmt_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct i2c_msg *pmsg; + int i; + int ret = 0; + struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + + for (i = 0; ret >= 0 && i < num; i++) { + pmsg = &msgs[i]; + if (!(pmsg->flags & I2C_M_NOSTART)) { + ret = wmt_i2c_wait_bus_not_busy(i2c_dev); + if (ret < 0) + return ret; + } + + if (pmsg->flags & I2C_M_RD) + ret = wmt_i2c_read(i2c_dev, pmsg); + else + ret = wmt_i2c_write(i2c_dev, pmsg, (i + 1) == num); + } + + return (ret < 0) ? ret : i; +} + +static irqreturn_t wmt_i2c_isr(int irq, void *data) +{ + struct wmt_i2c_dev *i2c_dev = data; + + /* save the status and write-clear it */ + i2c_dev->cmd_status = readw(i2c_dev->base + REG_ISR); + writew(i2c_dev->cmd_status, i2c_dev->base + REG_ISR); + + complete(&i2c_dev->complete); + + return IRQ_HANDLED; +} + +int wmt_i2c_init(struct platform_device *pdev, struct wmt_i2c_dev **pi2c_dev) +{ + int err; + struct wmt_i2c_dev *i2c_dev; + struct device_node *np = pdev->dev.of_node; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + i2c_dev->irq = irq_of_parse_and_map(np, 0); + if (!i2c_dev->irq) + return -EINVAL; + + err = devm_request_irq(&pdev->dev, i2c_dev->irq, wmt_i2c_isr, + 0, pdev->name, i2c_dev); + if (err) + return dev_err_probe(&pdev->dev, err, + "failed to request irq %i\n", i2c_dev->irq); + + i2c_dev->dev = &pdev->dev; + init_completion(&i2c_dev->complete); + platform_set_drvdata(pdev, i2c_dev); + + *pi2c_dev = i2c_dev; + return 0; +} diff --git a/drivers/i2c/busses/i2c-viai2c-common.h b/drivers/i2c/busses/i2c-viai2c-common.h new file mode 100644 index 000000000000..fcff8e4456eb --- /dev/null +++ b/drivers/i2c/busses/i2c-viai2c-common.h @@ -0,0 +1,71 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef __I2C_VIAI2C_COMMON_H_ +#define __I2C_VIAI2C_COMMON_H_ + +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> + +#define REG_CR 0x00 +#define REG_TCR 0x02 +#define REG_CSR 0x04 +#define REG_ISR 0x06 +#define REG_IMR 0x08 +#define REG_CDR 0x0A +#define REG_TR 0x0C +#define REG_MCR 0x0E + +/* REG_CR Bit fields */ +#define CR_TX_NEXT_ACK 0x0000 +#define CR_ENABLE 0x0001 +#define CR_TX_NEXT_NO_ACK 0x0002 +#define CR_TX_END 0x0004 +#define CR_CPU_RDY 0x0008 +#define SLAV_MODE_SEL 0x8000 + +/* REG_TCR Bit fields */ +#define TCR_STANDARD_MODE 0x0000 +#define TCR_MASTER_WRITE 0x0000 +#define TCR_HS_MODE 0x2000 +#define TCR_MASTER_READ 0x4000 +#define TCR_FAST_MODE 0x8000 +#define TCR_SLAVE_ADDR_MASK 0x007F + +/* REG_ISR Bit fields */ +#define ISR_NACK_ADDR 0x0001 +#define ISR_BYTE_END 0x0002 +#define ISR_SCL_TIMEOUT 0x0004 +#define ISR_WRITE_ALL 0x0007 + +/* REG_IMR Bit fields */ +#define IMR_ENABLE_ALL 0x0007 + +/* REG_CSR Bit fields */ +#define CSR_RCV_NOT_ACK 0x0001 +#define CSR_RCV_ACK_MASK 0x0001 +#define CSR_READY_MASK 0x0002 + +#define WMT_I2C_TIMEOUT (msecs_to_jiffies(1000)) + +struct wmt_i2c_dev { + struct i2c_adapter adapter; + struct completion complete; + struct device *dev; + void __iomem *base; + struct clk *clk; + u16 tcr; + int irq; + u16 cmd_status; +}; + +int wmt_i2c_wait_bus_not_busy(struct wmt_i2c_dev *i2c_dev); +int wmt_check_status(struct wmt_i2c_dev *i2c_dev); +int wmt_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num); +int wmt_i2c_init(struct platform_device *pdev, struct wmt_i2c_dev **pi2c_dev); + +#endif diff --git a/drivers/i2c/busses/i2c-viai2c-wmt.c b/drivers/i2c/busses/i2c-viai2c-wmt.c new file mode 100644 index 000000000000..1a80f38d0b88 --- /dev/null +++ b/drivers/i2c/busses/i2c-viai2c-wmt.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Wondermedia I2C Master Mode Driver + * + * Copyright (C) 2012 Tony Prisk <linux@xxxxxxxxxxxxxxx> + * + * Derived from GPLv2+ licensed source: + * - Copyright (C) 2008 WonderMedia Technologies, Inc. + */ + +#include <linux/clk.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include "i2c-viai2c-common.h" + +#define REG_SLAVE_CR 0x10 +#define REG_SLAVE_SR 0x12 +#define REG_SLAVE_ISR 0x14 +#define REG_SLAVE_IMR 0x16 +#define REG_SLAVE_DR 0x18 +#define REG_SLAVE_TR 0x1A + +/* REG_TR */ +#define SCL_TIMEOUT(x) (((x) & 0xFF) << 8) +#define TR_STD 0x0064 +#define TR_HS 0x0019 + +/* REG_MCR */ +#define MCR_APB_96M 7 +#define MCR_APB_166M 12 + +static u32 wmt_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm wmt_i2c_algo = { + .master_xfer = wmt_i2c_xfer, + .functionality = wmt_i2c_func, +}; + +static int wmt_i2c_reset_hardware(struct wmt_i2c_dev *i2c_dev) +{ + int err; + + err = clk_prepare_enable(i2c_dev->clk); + if (err) { + dev_err(i2c_dev->dev, "failed to enable clock\n"); + return err; + } + + err = clk_set_rate(i2c_dev->clk, 20000000); + if (err) { + dev_err(i2c_dev->dev, "failed to set clock = 20Mhz\n"); + clk_disable_unprepare(i2c_dev->clk); + return err; + } + + writew(0, i2c_dev->base + REG_CR); + writew(MCR_APB_166M, i2c_dev->base + REG_MCR); + writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR); + writew(IMR_ENABLE_ALL, i2c_dev->base + REG_IMR); + writew(CR_ENABLE, i2c_dev->base + REG_CR); + readw(i2c_dev->base + REG_CSR); /* read clear */ + writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR); + + if (i2c_dev->tcr == TCR_FAST_MODE) + writew(SCL_TIMEOUT(128) | TR_HS, i2c_dev->base + REG_TR); + else + writew(SCL_TIMEOUT(128) | TR_STD, i2c_dev->base + REG_TR); + + return 0; +} + +static int wmt_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct wmt_i2c_dev *i2c_dev; + struct i2c_adapter *adap; + int err; + u32 clk_rate; + + err = wmt_i2c_init(pdev, &i2c_dev); + if (err) + return err; + + i2c_dev->clk = of_clk_get(np, 0); + if (IS_ERR(i2c_dev->clk)) { + dev_err(&pdev->dev, "unable to request clock\n"); + return PTR_ERR(i2c_dev->clk); + } + + err = of_property_read_u32(np, "clock-frequency", &clk_rate); + if (!err && (clk_rate == I2C_MAX_FAST_MODE_FREQ)) + i2c_dev->tcr = TCR_FAST_MODE; + + adap = &i2c_dev->adapter; + i2c_set_adapdata(adap, i2c_dev); + strscpy(adap->name, "WMT I2C adapter", sizeof(adap->name)); + adap->owner = THIS_MODULE; + adap->algo = &wmt_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + err = wmt_i2c_reset_hardware(i2c_dev); + if (err) { + dev_err(&pdev->dev, "error initializing hardware\n"); + return err; + } + + return i2c_add_adapter(adap); +} + +static void wmt_i2c_remove(struct platform_device *pdev) +{ + struct wmt_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + /* Disable interrupts, clock and delete adapter */ + writew(0, i2c_dev->base + REG_IMR); + clk_disable_unprepare(i2c_dev->clk); + i2c_del_adapter(&i2c_dev->adapter); +} + +static const struct of_device_id wmt_i2c_dt_ids[] = { + { .compatible = "wm,wm8505-i2c" }, + { /* Sentinel */ }, +}; + +static struct platform_driver wmt_i2c_driver = { + .probe = wmt_i2c_probe, + .remove_new = wmt_i2c_remove, + .driver = { + .name = "wmt-i2c", + .of_match_table = wmt_i2c_dt_ids, + }, +}; + +module_platform_driver(wmt_i2c_driver); + +MODULE_DESCRIPTION("Wondermedia I2C master-mode bus adapter"); +MODULE_AUTHOR("Tony Prisk <linux@xxxxxxxxxxxxxxx>"); +MODULE_LICENSE("GPL"); +MODULE_DEVICE_TABLE(of, wmt_i2c_dt_ids); diff --git a/drivers/i2c/busses/i2c-wmt.c b/drivers/i2c/busses/i2c-wmt.c deleted file mode 100644 index f1888f100d83..000000000000 --- a/drivers/i2c/busses/i2c-wmt.c +++ /dev/null @@ -1,422 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * Wondermedia I2C Master Mode Driver - * - * Copyright (C) 2012 Tony Prisk <linux@xxxxxxxxxxxxxxx> - * - * Derived from GPLv2+ licensed source: - * - Copyright (C) 2008 WonderMedia Technologies, Inc. - */ - -#include <linux/clk.h> -#include <linux/delay.h> -#include <linux/err.h> -#include <linux/i2c.h> -#include <linux/interrupt.h> -#include <linux/io.h> -#include <linux/module.h> -#include <linux/of.h> -#include <linux/of_address.h> -#include <linux/of_irq.h> -#include <linux/platform_device.h> - -#define REG_CR 0x00 -#define REG_TCR 0x02 -#define REG_CSR 0x04 -#define REG_ISR 0x06 -#define REG_IMR 0x08 -#define REG_CDR 0x0A -#define REG_TR 0x0C -#define REG_MCR 0x0E -#define REG_SLAVE_CR 0x10 -#define REG_SLAVE_SR 0x12 -#define REG_SLAVE_ISR 0x14 -#define REG_SLAVE_IMR 0x16 -#define REG_SLAVE_DR 0x18 -#define REG_SLAVE_TR 0x1A - -/* REG_CR Bit fields */ -#define CR_TX_NEXT_ACK 0x0000 -#define CR_ENABLE 0x0001 -#define CR_TX_NEXT_NO_ACK 0x0002 -#define CR_TX_END 0x0004 -#define CR_CPU_RDY 0x0008 -#define SLAV_MODE_SEL 0x8000 - -/* REG_TCR Bit fields */ -#define TCR_STANDARD_MODE 0x0000 -#define TCR_MASTER_WRITE 0x0000 -#define TCR_HS_MODE 0x2000 -#define TCR_MASTER_READ 0x4000 -#define TCR_FAST_MODE 0x8000 -#define TCR_SLAVE_ADDR_MASK 0x007F - -/* REG_ISR Bit fields */ -#define ISR_NACK_ADDR 0x0001 -#define ISR_BYTE_END 0x0002 -#define ISR_SCL_TIMEOUT 0x0004 -#define ISR_WRITE_ALL 0x0007 - -/* REG_IMR Bit fields */ -#define IMR_ENABLE_ALL 0x0007 - -/* REG_CSR Bit fields */ -#define CSR_RCV_NOT_ACK 0x0001 -#define CSR_RCV_ACK_MASK 0x0001 -#define CSR_READY_MASK 0x0002 - -/* REG_TR */ -#define SCL_TIMEOUT(x) (((x) & 0xFF) << 8) -#define TR_STD 0x0064 -#define TR_HS 0x0019 - -/* REG_MCR */ -#define MCR_APB_96M 7 -#define MCR_APB_166M 12 - -#define WMT_I2C_TIMEOUT (msecs_to_jiffies(1000)) - -struct wmt_i2c_dev { - struct i2c_adapter adapter; - struct completion complete; - struct device *dev; - void __iomem *base; - struct clk *clk; - u16 tcr; - int irq; - u16 cmd_status; -}; - -static int wmt_i2c_wait_bus_not_busy(struct wmt_i2c_dev *i2c_dev) -{ - unsigned long timeout; - - timeout = jiffies + WMT_I2C_TIMEOUT; - while (!(readw(i2c_dev->base + REG_CSR) & CSR_READY_MASK)) { - if (time_after(jiffies, timeout)) { - dev_warn(i2c_dev->dev, "timeout waiting for bus ready\n"); - return -EBUSY; - } - msleep(20); - } - - return 0; -} - -static int wmt_check_status(struct wmt_i2c_dev *i2c_dev) -{ - int ret = 0; - unsigned long wait_result; - - wait_result = wait_for_completion_timeout(&i2c_dev->complete, - msecs_to_jiffies(500)); - if (!wait_result) - return -ETIMEDOUT; - - if (i2c_dev->cmd_status & ISR_NACK_ADDR) - ret = -EIO; - - if (i2c_dev->cmd_status & ISR_SCL_TIMEOUT) - ret = -ETIMEDOUT; - - return ret; -} - -static int wmt_i2c_write(struct wmt_i2c_dev *i2c_dev, struct i2c_msg *pmsg, - int last) -{ - u16 val, tcr_val = i2c_dev->tcr; - int ret; - int xfer_len = 0; - - if (pmsg->len == 0) { - /* - * We still need to run through the while (..) once, so - * start at -1 and break out early from the loop - */ - xfer_len = -1; - writew(0, i2c_dev->base + REG_CDR); - } else { - writew(pmsg->buf[0] & 0xFF, i2c_dev->base + REG_CDR); - } - - if (!(pmsg->flags & I2C_M_NOSTART)) { - val = readw(i2c_dev->base + REG_CR); - val &= ~CR_TX_END; - val |= CR_CPU_RDY; - writew(val, i2c_dev->base + REG_CR); - } - - reinit_completion(&i2c_dev->complete); - - tcr_val |= (TCR_MASTER_WRITE | (pmsg->addr & TCR_SLAVE_ADDR_MASK)); - - writew(tcr_val, i2c_dev->base + REG_TCR); - - if (pmsg->flags & I2C_M_NOSTART) { - val = readw(i2c_dev->base + REG_CR); - val |= CR_CPU_RDY; - writew(val, i2c_dev->base + REG_CR); - } - - while (xfer_len < pmsg->len) { - ret = wmt_check_status(i2c_dev); - if (ret) - return ret; - - xfer_len++; - - val = readw(i2c_dev->base + REG_CSR); - if ((val & CSR_RCV_ACK_MASK) == CSR_RCV_NOT_ACK) { - dev_dbg(i2c_dev->dev, "write RCV NACK error\n"); - return -EIO; - } - - if (pmsg->len == 0) { - val = CR_TX_END | CR_CPU_RDY | CR_ENABLE; - writew(val, i2c_dev->base + REG_CR); - break; - } - - if (xfer_len == pmsg->len) { - if (last != 1) - writew(CR_ENABLE, i2c_dev->base + REG_CR); - } else { - writew(pmsg->buf[xfer_len] & 0xFF, i2c_dev->base + - REG_CDR); - writew(CR_CPU_RDY | CR_ENABLE, i2c_dev->base + REG_CR); - } - } - - return 0; -} - -static int wmt_i2c_read(struct wmt_i2c_dev *i2c_dev, struct i2c_msg *pmsg) -{ - u16 val, tcr_val = i2c_dev->tcr; - int ret; - u32 xfer_len = 0; - - val = readw(i2c_dev->base + REG_CR); - val &= ~(CR_TX_END | CR_TX_NEXT_NO_ACK); - - if (!(pmsg->flags & I2C_M_NOSTART)) - val |= CR_CPU_RDY; - - if (pmsg->len == 1) - val |= CR_TX_NEXT_NO_ACK; - - writew(val, i2c_dev->base + REG_CR); - - reinit_completion(&i2c_dev->complete); - - tcr_val |= TCR_MASTER_READ | (pmsg->addr & TCR_SLAVE_ADDR_MASK); - - writew(tcr_val, i2c_dev->base + REG_TCR); - - if (pmsg->flags & I2C_M_NOSTART) { - val = readw(i2c_dev->base + REG_CR); - val |= CR_CPU_RDY; - writew(val, i2c_dev->base + REG_CR); - } - - while (xfer_len < pmsg->len) { - ret = wmt_check_status(i2c_dev); - if (ret) - return ret; - - pmsg->buf[xfer_len] = readw(i2c_dev->base + REG_CDR) >> 8; - xfer_len++; - - val = readw(i2c_dev->base + REG_CR) | CR_CPU_RDY; - if (xfer_len == pmsg->len - 1) - val |= CR_TX_NEXT_NO_ACK; - writew(val, i2c_dev->base + REG_CR); - } - - return 0; -} - -static int wmt_i2c_xfer(struct i2c_adapter *adap, - struct i2c_msg msgs[], - int num) -{ - struct i2c_msg *pmsg; - int i; - int ret = 0; - struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap); - - for (i = 0; ret >= 0 && i < num; i++) { - pmsg = &msgs[i]; - if (!(pmsg->flags & I2C_M_NOSTART)) { - ret = wmt_i2c_wait_bus_not_busy(i2c_dev); - if (ret < 0) - return ret; - } - - if (pmsg->flags & I2C_M_RD) - ret = wmt_i2c_read(i2c_dev, pmsg); - else - ret = wmt_i2c_write(i2c_dev, pmsg, (i + 1) == num); - } - - return (ret < 0) ? ret : i; -} - -static u32 wmt_i2c_func(struct i2c_adapter *adap) -{ - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART; -} - -static const struct i2c_algorithm wmt_i2c_algo = { - .master_xfer = wmt_i2c_xfer, - .functionality = wmt_i2c_func, -}; - -static irqreturn_t wmt_i2c_isr(int irq, void *data) -{ - struct wmt_i2c_dev *i2c_dev = data; - - /* save the status and write-clear it */ - i2c_dev->cmd_status = readw(i2c_dev->base + REG_ISR); - writew(i2c_dev->cmd_status, i2c_dev->base + REG_ISR); - - complete(&i2c_dev->complete); - - return IRQ_HANDLED; -} - -static int wmt_i2c_init(struct platform_device *pdev, struct wmt_i2c_dev **pi2c_dev) -{ - int err; - struct wmt_i2c_dev *i2c_dev; - struct device_node *np = pdev->dev.of_node; - - i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); - if (!i2c_dev) - return -ENOMEM; - - i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); - if (IS_ERR(i2c_dev->base)) - return PTR_ERR(i2c_dev->base); - - i2c_dev->irq = irq_of_parse_and_map(np, 0); - if (!i2c_dev->irq) - return -EINVAL; - - err = devm_request_irq(&pdev->dev, i2c_dev->irq, wmt_i2c_isr, - 0, pdev->name, i2c_dev); - if (err) - return dev_err_probe(&pdev->dev, err, - "failed to request irq %i\n", i2c_dev->irq); - - i2c_dev->dev = &pdev->dev; - init_completion(&i2c_dev->complete); - platform_set_drvdata(pdev, i2c_dev); - - *pi2c_dev = i2c_dev; - return 0; -} - -static int wmt_i2c_reset_hardware(struct wmt_i2c_dev *i2c_dev) -{ - int err; - - err = clk_prepare_enable(i2c_dev->clk); - if (err) { - dev_err(i2c_dev->dev, "failed to enable clock\n"); - return err; - } - - err = clk_set_rate(i2c_dev->clk, 20000000); - if (err) { - dev_err(i2c_dev->dev, "failed to set clock = 20Mhz\n"); - clk_disable_unprepare(i2c_dev->clk); - return err; - } - - writew(0, i2c_dev->base + REG_CR); - writew(MCR_APB_166M, i2c_dev->base + REG_MCR); - writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR); - writew(IMR_ENABLE_ALL, i2c_dev->base + REG_IMR); - writew(CR_ENABLE, i2c_dev->base + REG_CR); - readw(i2c_dev->base + REG_CSR); /* read clear */ - writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR); - - if (i2c_dev->tcr == TCR_FAST_MODE) - writew(SCL_TIMEOUT(128) | TR_HS, i2c_dev->base + REG_TR); - else - writew(SCL_TIMEOUT(128) | TR_STD, i2c_dev->base + REG_TR); - - return 0; -} - -static int wmt_i2c_probe(struct platform_device *pdev) -{ - struct device_node *np = pdev->dev.of_node; - struct wmt_i2c_dev *i2c_dev; - struct i2c_adapter *adap; - int err; - u32 clk_rate; - - err = wmt_i2c_init(pdev, &i2c_dev); - if (err) - return err; - - i2c_dev->clk = of_clk_get(np, 0); - if (IS_ERR(i2c_dev->clk)) { - dev_err(&pdev->dev, "unable to request clock\n"); - return PTR_ERR(i2c_dev->clk); - } - - err = of_property_read_u32(np, "clock-frequency", &clk_rate); - if (!err && (clk_rate == I2C_MAX_FAST_MODE_FREQ)) - i2c_dev->tcr = TCR_FAST_MODE; - - adap = &i2c_dev->adapter; - i2c_set_adapdata(adap, i2c_dev); - strscpy(adap->name, "WMT I2C adapter", sizeof(adap->name)); - adap->owner = THIS_MODULE; - adap->algo = &wmt_i2c_algo; - adap->dev.parent = &pdev->dev; - adap->dev.of_node = pdev->dev.of_node; - - err = wmt_i2c_reset_hardware(i2c_dev); - if (err) { - dev_err(&pdev->dev, "error initializing hardware\n"); - return err; - } - - return i2c_add_adapter(adap); -} - -static void wmt_i2c_remove(struct platform_device *pdev) -{ - struct wmt_i2c_dev *i2c_dev = platform_get_drvdata(pdev); - - /* Disable interrupts, clock and delete adapter */ - writew(0, i2c_dev->base + REG_IMR); - clk_disable_unprepare(i2c_dev->clk); - i2c_del_adapter(&i2c_dev->adapter); -} - -static const struct of_device_id wmt_i2c_dt_ids[] = { - { .compatible = "wm,wm8505-i2c" }, - { /* Sentinel */ }, -}; - -static struct platform_driver wmt_i2c_driver = { - .probe = wmt_i2c_probe, - .remove_new = wmt_i2c_remove, - .driver = { - .name = "wmt-i2c", - .of_match_table = wmt_i2c_dt_ids, - }, -}; - -module_platform_driver(wmt_i2c_driver); - -MODULE_DESCRIPTION("Wondermedia I2C master-mode bus adapter"); -MODULE_AUTHOR("Tony Prisk <linux@xxxxxxxxxxxxxxx>"); -MODULE_LICENSE("GPL"); -MODULE_DEVICE_TABLE(of, wmt_i2c_dt_ids); -- 2.34.1
