RE: [PATCH v2 04/22] HID: intel-thc-hid: intel-thc: Add THC PIO operation APIs

From: Xu, Even
Date: Wed Dec 04 2024 - 01:00:25 EST




> -----Original Message-----
> From: Aaron Ma <aaron.ma@xxxxxxxxxxxxx>
> Sent: Wednesday, December 4, 2024 1:37 PM
> To: Xu, Even <even.xu@xxxxxxxxx>; jikos@xxxxxxxxxx; bentiss@xxxxxxxxxx;
> corbet@xxxxxxx; bagasdotme@xxxxxxxxx
> Cc: linux-input@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> doc@xxxxxxxxxxxxxxx; Sun, Xinpeng <xinpeng.sun@xxxxxxxxx>; Zhang, Rui1
> <rui1.zhang@xxxxxxxxx>; Srinivas Pandruvada
> <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> Subject: Re: [PATCH v2 04/22] HID: intel-thc-hid: intel-thc: Add THC PIO operation
> APIs
>
>
>
> On 11/14/24 1:33 PM, Even Xu wrote:
> > From: Xinpeng Sun <xinpeng.sun@xxxxxxxxx>
> >
> > THC PIO (programmed I/O) operations are very similar with general
> > SPI/I2C read/write operation to access external slave device on the
> > bus through internal FIFO.
> >
> > THC PIO operations are split into 4 steps:
> > 1. prepare: configure hardware with correct opcode, slave address, and
> > fill the PIO FIFO
> > 2. start: set start bit to issue a bus send/receive 3. wait: wait for
> > bus sending/receiving completion 4. complete: check send/receive data
> > in FIFO and return
> >
> > Co-developed-by: Even Xu <even.xu@xxxxxxxxx>
> > Signed-off-by: Even Xu <even.xu@xxxxxxxxx>
> > Signed-off-by: Xinpeng Sun <xinpeng.sun@xxxxxxxxx>
> > Tested-by: Rui Zhang <rui1.zhang@xxxxxxxxx>
> > Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> > ---
> > .../intel-thc-hid/intel-thc/intel-thc-dev.c | 245 ++++++++++++++++++
> > .../intel-thc-hid/intel-thc/intel-thc-dev.h | 24 ++
> > .../intel-thc-hid/intel-thc/intel-thc-hw.h | 23 ++
> > 3 files changed, 292 insertions(+)
> >
> > diff --git a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.c
> > b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.c
> > index d77603e4c01e..0571b8270716 100644
> > --- a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.c
> > +++ b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.c
> > @@ -1,9 +1,11 @@
> > /* SPDX-License-Identifier: GPL-2.0 */
> > /* Copyright (c) 2024 Intel Corporation */
> >
> > +#include <linux/bitfield.h>
> > #include <linux/regmap.h>
> >
> > #include "intel-thc-dev.h"
> > +#include "intel-thc-hw.h"
> >
> > static int thc_regmap_read(void *context, unsigned int reg,
> > unsigned int *val)
> > @@ -76,10 +78,253 @@ struct thc_device *thc_dev_init(struct device *device,
> void __iomem *mem_addr)
> > return ERR_PTR(ret);
> > }
> >
> > + mutex_init(&thc_dev->thc_bus_lock);
> > +
> > return thc_dev;
> > }
> > EXPORT_SYMBOL_NS_GPL(thc_dev_init, INTEL_THC);
>
>
>
> Since the commit in 6.13-rc1+ change the symbol namespace:
> cdd30ebb1b9f ("module: Convert symbol namespace to string literal")
>
> This should be changed to
> EXPORT_SYMBOL_NS_GPL(thc_dev_init, "INTEL_THC");
>
> There are many of them in this driver, better to define a helper macro in header
> file.
> And group them consistently.
>
> Aaron
>

Thanks for the information!
Just go through the convert patch, let me do the change by script.

Best Regards,
Even Xu


>
> >
> > +static int prepare_pio(const struct thc_device *dev, const u8 pio_op,
> > + const u32 address, const u32 size) {
> > + u32 sts, ctrl, addr, mask;
> > +
> > + regmap_read(dev->thc_regmap, THC_M_PRT_SW_SEQ_STS_OFFSET,
> &sts);
> > +
> > + /* Check if THC previous PIO still in progress */
> > + if (sts & THC_M_PRT_SW_SEQ_STS_THC_SS_CIP) {
> > + dev_err_once(dev->dev, "THC PIO is still busy!\n");
> > + return -EBUSY;
> > + }
> > +
> > + /* Clear error bit and complete bit in state register */
> > + sts |= THC_M_PRT_SW_SEQ_STS_THC_SS_ERR |
> > + THC_M_PRT_SW_SEQ_STS_TSSDONE;
> > + regmap_write(dev->thc_regmap, THC_M_PRT_SW_SEQ_STS_OFFSET,
> sts);
> > +
> > + /* Set PIO data size, opcode and interrupt capability */
> > + ctrl = FIELD_PREP(THC_M_PRT_SW_SEQ_CNTRL_THC_SS_BC, size) |
> > + FIELD_PREP(THC_M_PRT_SW_SEQ_CNTRL_THC_SS_CMD, pio_op);
> > + if (dev->pio_int_supported)
> > + ctrl |= THC_M_PRT_SW_SEQ_CNTRL_THC_SS_CD_IE;
> > +
> > + mask = THC_M_PRT_SW_SEQ_CNTRL_THC_SS_BC |
> > + THC_M_PRT_SW_SEQ_CNTRL_THC_SS_CMD |
> > + THC_M_PRT_SW_SEQ_CNTRL_THC_SS_CD_IE;
> > + regmap_write_bits(dev->thc_regmap,
> > + THC_M_PRT_SW_SEQ_CNTRL_OFFSET, mask, ctrl);
> > +
> > + /* Set PIO target address */
> > + addr =
> FIELD_PREP(THC_M_PRT_SW_SEQ_DATA0_ADDR_THC_SW_SEQ_DATA0_ADDR,
> address);
> > + mask =
> THC_M_PRT_SW_SEQ_DATA0_ADDR_THC_SW_SEQ_DATA0_ADDR;
> > + regmap_write_bits(dev->thc_regmap,
> > + THC_M_PRT_SW_SEQ_DATA0_ADDR_OFFSET, mask,
> addr);
> > + return 0;
> > +}
> > +
> > +static void pio_start(const struct thc_device *dev,
> > + u32 size_in_bytes, const u32 *buffer) {
> > + if (size_in_bytes && buffer)
> > + regmap_bulk_write(dev->thc_regmap,
> THC_M_PRT_SW_SEQ_DATA1_OFFSET,
> > + buffer, size_in_bytes / sizeof(u32));
> > +
> > + /* Enable Start bit */
> > + regmap_write_bits(dev->thc_regmap,
> > + THC_M_PRT_SW_SEQ_CNTRL_OFFSET,
> > + THC_M_PRT_SW_SEQ_CNTRL_TSSGO,
> > + THC_M_PRT_SW_SEQ_CNTRL_TSSGO);
> > +}
> > +
> > +static int pio_complete(const struct thc_device *dev,
> > + u32 *buffer, u32 *size)
> > +{
> > + u32 sts, ctrl;
> > +
> > + regmap_read(dev->thc_regmap, THC_M_PRT_SW_SEQ_STS_OFFSET,
> &sts);
> > + if (sts & THC_M_PRT_SW_SEQ_STS_THC_SS_ERR) {
> > + dev_err_once(dev->dev, "PIO operation error\n");
> > + return -EBUSY;
> > + }
> > +
> > + if (buffer && size) {
> > + regmap_read(dev->thc_regmap,
> THC_M_PRT_SW_SEQ_CNTRL_OFFSET, &ctrl);
> > + *size = FIELD_GET(THC_M_PRT_SW_SEQ_CNTRL_THC_SS_BC,
> ctrl);
> > +
> > + regmap_bulk_read(dev->thc_regmap,
> THC_M_PRT_SW_SEQ_DATA1_OFFSET,
> > + buffer, *size / sizeof(u32));
> > + }
> > +
> > + sts |= THC_M_PRT_SW_SEQ_STS_THC_SS_ERR |
> THC_M_PRT_SW_SEQ_STS_TSSDONE;
> > + regmap_write(dev->thc_regmap, THC_M_PRT_SW_SEQ_STS_OFFSET,
> sts);
> > + return 0;
> > +}
> > +
> > +static int pio_wait(const struct thc_device *dev) {
> > + u32 sts = 0;
> > + int ret;
> > +
> > + ret = regmap_read_poll_timeout(dev->thc_regmap,
> THC_M_PRT_SW_SEQ_STS_OFFSET, sts,
> > + !(sts &
> THC_M_PRT_SW_SEQ_STS_THC_SS_CIP ||
> > + !(sts &
> THC_M_PRT_SW_SEQ_STS_TSSDONE)),
> > + THC_REGMAP_POLLING_INTERVAL_US,
> THC_PIO_DONE_TIMEOUT_US);
> > + if (ret)
> > + dev_err_once(dev->dev, "Timeout while polling PIO operation
> > +done\n");
> > +
> > + return ret;
> > +}
> > +
> > +/**
> > + * thc_tic_pio_read - Read data from touch device by PIO
> > + *
> > + * @dev: The pointer of THC private device context
> > + * @address: Slave address for the PIO operation
> > + * @size: Expected read data size
> > + * @actual_size: The pointer of the actual data size read from touch
> > +device
> > + * @buffer: The pointer of data buffer to store the data read from
> > +touch device
> > + *
> > + * Return: 0 on success, other error codes on failed.
> > + */
> > +int thc_tic_pio_read(struct thc_device *dev, const u32 address,
> > + const u32 size, u32 *actual_size, u32 *buffer) {
> > + u8 opcode;
> > + int ret;
> > +
> > + if (size <= 0 || !actual_size || !buffer) {
> > + dev_err(dev->dev, "Invalid input parameters, size %u,
> actual_size %p, buffer %p\n",
> > + size, actual_size, buffer);
> > + return -EINVAL;
> > + }
> > +
> > + if (mutex_lock_interruptible(&dev->thc_bus_lock))
> > + return -EINTR;
> > +
> > + opcode = (dev->port_type == THC_PORT_TYPE_SPI) ?
> > + THC_PIO_OP_SPI_TIC_READ : THC_PIO_OP_I2C_TIC_READ;
> > +
> > + ret = prepare_pio(dev, opcode, address, size);
> > + if (ret < 0)
> > + goto end;
> > +
> > + pio_start(dev, 0, NULL);
> > +
> > + ret = pio_wait(dev);
> > + if (ret < 0)
> > + goto end;
> > +
> > + ret = pio_complete(dev, buffer, actual_size);
> > +
> > +end:
> > + mutex_unlock(&dev->thc_bus_lock);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_NS_GPL(thc_tic_pio_read, INTEL_THC);
> > +
> > +/**
> > + * thc_tic_pio_write - Write data to touch device by PIO
> > + *
> > + * @dev: The pointer of THC private device context
> > + * @address: Slave address for the PIO operation
> > + * @size: PIO write data size
> > + * @buffer: The pointer of the write data buffer
> > + *
> > + * Return: 0 on success, other error codes on failed.
> > + */
> > +int thc_tic_pio_write(struct thc_device *dev, const u32 address,
> > + const u32 size, const u32 *buffer) {
> > + u8 opcode;
> > + int ret;
> > +
> > + if (size <= 0 || !buffer) {
> > + dev_err(dev->dev, "Invalid input parameters, size %u,
> buffer %p\n",
> > + size, buffer);
> > + return -EINVAL;
> > + }
> > +
> > + if (mutex_lock_interruptible(&dev->thc_bus_lock))
> > + return -EINTR;
> > +
> > + opcode = (dev->port_type == THC_PORT_TYPE_SPI) ?
> > + THC_PIO_OP_SPI_TIC_WRITE : THC_PIO_OP_I2C_TIC_WRITE;
> > +
> > + ret = prepare_pio(dev, opcode, address, size);
> > + if (ret < 0)
> > + goto end;
> > +
> > + pio_start(dev, size, buffer);
> > +
> > + ret = pio_wait(dev);
> > + if (ret < 0)
> > + goto end;
> > +
> > + ret = pio_complete(dev, NULL, NULL);
> > +
> > +end:
> > + mutex_unlock(&dev->thc_bus_lock);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_NS_GPL(thc_tic_pio_write, INTEL_THC);
> > +
> > +/**
> > + * thc_tic_pio_write_and_read - Write data followed by read data by
> > +PIO
> > + *
> > + * @dev: The pointer of THC private device context
> > + * @address: Slave address for the PIO operation
> > + * @write_size: PIO write data size
> > + * @write_buffer: The pointer of the write data buffer
> > + * @read_size: Expected PIO read data size
> > + * @actual_size: The pointer of the actual read data size
> > + * @read_buffer: The pointer of PIO read data buffer
> > + *
> > + * Return: 0 on success, other error codes on failed.
> > + */
> > +int thc_tic_pio_write_and_read(struct thc_device *dev, const u32 address,
> > + const u32 write_size, const u32 *write_buffer,
> > + const u32 read_size, u32 *actual_size, u32
> *read_buffer) {
> > + u32 i2c_ctrl, mask;
> > + int ret;
> > +
> > + if (dev->port_type == THC_PORT_TYPE_SPI) {
> > + dev_err(dev->dev, "SPI port type doesn't support pio write and
> read!");
> > + return -EINVAL;
> > + }
> > +
> > + if (mutex_lock_interruptible(&dev->thc_bus_lock))
> > + return -EINTR;
> > +
> > + /* Config i2c PIO write and read sequence */
> > + i2c_ctrl =
> FIELD_PREP(THC_M_PRT_SW_SEQ_I2C_WR_CNTRL_THC_PIO_I2C_WBC,
> write_size);
> > + mask = THC_M_PRT_SW_SEQ_I2C_WR_CNTRL_THC_PIO_I2C_WBC;
> > +
> > + regmap_write_bits(dev->thc_regmap,
> THC_M_PRT_SW_SEQ_I2C_WR_CNTRL_OFFSET,
> > + mask, i2c_ctrl);
> > +
> > + regmap_write_bits(dev->thc_regmap,
> THC_M_PRT_SW_SEQ_I2C_WR_CNTRL_OFFSET,
> > +
> THC_M_PRT_SW_SEQ_I2C_WR_CNTRL_THC_I2C_RW_PIO_EN,
> > +
> THC_M_PRT_SW_SEQ_I2C_WR_CNTRL_THC_I2C_RW_PIO_EN);
> > +
> > + ret = prepare_pio(dev, THC_PIO_OP_I2C_TIC_WRITE_AND_READ,
> address, read_size);
> > + if (ret < 0)
> > + goto end;
> > +
> > + pio_start(dev, write_size, write_buffer);
> > +
> > + ret = pio_wait(dev);
> > + if (ret < 0)
> > + goto end;
> > +
> > + ret = pio_complete(dev, read_buffer, actual_size);
> > +
> > +end:
> > + mutex_unlock(&dev->thc_bus_lock);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_NS_GPL(thc_tic_pio_write_and_read, INTEL_THC);
> > +
> > MODULE_AUTHOR("Xinpeng Sun <xinpeng.sun@xxxxxxxxx>");
> > MODULE_AUTHOR("Even Xu <even.xu@xxxxxxxxx>");
> >
> > diff --git a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.h
> > b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.h
> > index 7060f0a36cbd..88a9f606a6a9 100644
> > --- a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.h
> > +++ b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dev.h
> > @@ -5,21 +5,45 @@
> > #define _INTEL_THC_DEV_H_
> >
> > #include <linux/cdev.h>
> > +#include <linux/mutex.h>
> >
> > #define THC_REGMAP_COMMON_OFFSET 0x10
> > #define THC_REGMAP_MMIO_OFFSET 0x1000
> >
> > +/*
> > + * THC Port type
> > + * @THC_PORT_TYPE_SPI: This port is used for HIDSPI
> > + * @THC_PORT_TYPE_I2C: This port is used for HIDI2C */ enum
> > +thc_port_type {
> > + THC_PORT_TYPE_SPI = 0,
> > + THC_PORT_TYPE_I2C = 1,
> > +};
> > +
> > /**
> > * struct thc_device - THC private device struct
> > * @thc_regmap: MMIO regmap structure for accessing THC registers
> > * @mmio_addr: MMIO registers address
> > + * @thc_bus_lock: mutex locker for THC config
> > + * @port_type: port type of THC port instance
> > + * @pio_int_supported: PIO interrupt supported flag
> > */
> > struct thc_device {
> > struct device *dev;
> > struct regmap *thc_regmap;
> > void __iomem *mmio_addr;
> > + struct mutex thc_bus_lock;
> > + enum thc_port_type port_type;
> > + bool pio_int_supported;
> > };
> >
> > struct thc_device *thc_dev_init(struct device *device, void __iomem
> > *mem_addr);
> > +int thc_tic_pio_read(struct thc_device *dev, const u32 address,
> > + const u32 size, u32 *actual_size, u32 *buffer); int
> > +thc_tic_pio_write(struct thc_device *dev, const u32 address,
> > + const u32 size, const u32 *buffer); int
> > +thc_tic_pio_write_and_read(struct thc_device *dev, const u32 address,
> > + const u32 write_size, const u32 *write_buffer,
> > + const u32 read_size, u32 *actual_size, u32
> *read_buffer);
> >
> > #endif /* _INTEL_THC_DEV_H_ */
> > diff --git a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-hw.h
> > b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-hw.h
> > index 77b275a400d5..9f5f39dcedcd 100644
> > --- a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-hw.h
> > +++ b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-hw.h
> > @@ -633,4 +633,27 @@
> >
> > #define
> THC_M_PRT_SW_DMA_PRD_TABLE_LEN_THC_M_PRT_SW_DMA_PRD_TABLE_L
> EN GENMASK(23, 0)
> >
> > +#define THC_REGMAP_POLLING_INTERVAL_US 10 /* 10us */
> > +#define THC_PIO_DONE_TIMEOUT_US
> USEC_PER_SEC /* 1s */
> > +
> > +/*
> > + * THC PIO opcode default value
> > + * @THC_PIO_OP_SPI_TIC_READ: THC opcode for SPI PIO read
> > + * @THC_PIO_OP_SPI_TIC_WRITE: THC opcode for SPI PIO write
> > + * @THC_PIO_OP_I2C_SUBSYSTEM_READ: THC opcode for read I2C
> subsystem
> > +registers
> > + * @THC_PIO_OP_I2C_SUBSYSTEM_WRITE: THC opcode for write I2C
> > +subsystem registers
> > + * @THC_PIO_OP_I2C_TIC_READ: THC opcode for read I2C device
> > + * @THC_PIO_OP_I2C_TIC_WRITE: THC opcode for write I2C device
> > + * @THC_PIO_OP_I2C_TIC_WRITE_AND_READ: THC opcode for write
> followed
> > +by read I2C device */ enum thc_pio_opcode {
> > + THC_PIO_OP_SPI_TIC_READ = 0x4,
> > + THC_PIO_OP_SPI_TIC_WRITE = 0x6,
> > + THC_PIO_OP_I2C_SUBSYSTEM_READ = 0x12,
> > + THC_PIO_OP_I2C_SUBSYSTEM_WRITE = 0x13,
> > + THC_PIO_OP_I2C_TIC_READ = 0x14,
> > + THC_PIO_OP_I2C_TIC_WRITE = 0x18,
> > + THC_PIO_OP_I2C_TIC_WRITE_AND_READ = 0x1C, };
> > +
> > #endif /* _INTEL_THC_HW_H_ */