From e4c6eb68343fb1cfe4bffc6802180e91826f76af Mon Sep 17 00:00:00 2001 From: Min Li Date: Thu, 5 Nov 2020 22:52:08 -0500 Subject: [PATCH] ptp: idt82p33: use i2c_master_send for bus write Refactor idt82p33_xfer and use i2c_master_send for write operation. Because some I2C controllers are only working with single-burst write transaction. Signed-off-by: Min Li Acked-by: Richard Cochran Link: https://lore.kernel.org/r/1604634729-24960-2-git-send-email-min.li.xe@renesas.com Signed-off-by: Jakub Kicinski --- drivers/ptp/ptp_idt82p33.c | 47 +++++++++++++++++++++++++++++++++++----------- drivers/ptp/ptp_idt82p33.h | 1 + 2 files changed, 37 insertions(+), 11 deletions(-) diff --git a/drivers/ptp/ptp_idt82p33.c b/drivers/ptp/ptp_idt82p33.c index 50af339..223bc11 100644 --- a/drivers/ptp/ptp_idt82p33.c +++ b/drivers/ptp/ptp_idt82p33.c @@ -78,11 +78,10 @@ static void idt82p33_timespec_to_byte_array(struct timespec64 const *ts, } } -static int idt82p33_xfer(struct idt82p33 *idt82p33, - unsigned char regaddr, - unsigned char *buf, - unsigned int count, - int write) +static int idt82p33_xfer_read(struct idt82p33 *idt82p33, + unsigned char regaddr, + unsigned char *buf, + unsigned int count) { struct i2c_client *client = idt82p33->client; struct i2c_msg msg[2]; @@ -94,7 +93,7 @@ static int idt82p33_xfer(struct idt82p33 *idt82p33, msg[0].buf = ®addr; msg[1].addr = client->addr; - msg[1].flags = write ? 0 : I2C_M_RD; + msg[1].flags = I2C_M_RD; msg[1].len = count; msg[1].buf = buf; @@ -110,6 +109,31 @@ static int idt82p33_xfer(struct idt82p33 *idt82p33, return 0; } +static int idt82p33_xfer_write(struct idt82p33 *idt82p33, + u8 regaddr, + u8 *buf, + u16 count) +{ + struct i2c_client *client = idt82p33->client; + /* we add 1 byte for device register */ + u8 msg[IDT82P33_MAX_WRITE_COUNT + 1]; + int err; + + if (count > IDT82P33_MAX_WRITE_COUNT) + return -EINVAL; + + msg[0] = regaddr; + memcpy(&msg[1], buf, count); + + err = i2c_master_send(client, msg, count + 1); + if (err < 0) { + dev_err(&client->dev, "i2c_master_send returned %d\n", err); + return err; + } + + return 0; +} + static int idt82p33_page_offset(struct idt82p33 *idt82p33, unsigned char val) { int err; @@ -117,7 +141,7 @@ static int idt82p33_page_offset(struct idt82p33 *idt82p33, unsigned char val) if (idt82p33->page_offset == val) return 0; - err = idt82p33_xfer(idt82p33, PAGE_ADDR, &val, sizeof(val), 1); + err = idt82p33_xfer_write(idt82p33, PAGE_ADDR, &val, sizeof(val)); if (err) dev_err(&idt82p33->client->dev, "failed to set page offset %d\n", val); @@ -138,11 +162,12 @@ static int idt82p33_rdwr(struct idt82p33 *idt82p33, unsigned int regaddr, err = idt82p33_page_offset(idt82p33, page); if (err) - goto out; + return err; - err = idt82p33_xfer(idt82p33, offset, buf, count, write); -out: - return err; + if (write) + return idt82p33_xfer_write(idt82p33, offset, buf, count); + + return idt82p33_xfer_read(idt82p33, offset, buf, count); } static int idt82p33_read(struct idt82p33 *idt82p33, unsigned int regaddr, diff --git a/drivers/ptp/ptp_idt82p33.h b/drivers/ptp/ptp_idt82p33.h index 3a0e001..1c7a0f0 100644 --- a/drivers/ptp/ptp_idt82p33.h +++ b/drivers/ptp/ptp_idt82p33.h @@ -95,6 +95,7 @@ enum hw_tod_trig_sel { #define MAX_MEASURMENT_COUNT (5) #define SNAP_THRESHOLD_NS (150000) #define SYNC_TOD_TIMEOUT_SEC (5) +#define IDT82P33_MAX_WRITE_COUNT (512) #define PLLMASK_ADDR_HI 0xFF #define PLLMASK_ADDR_LO 0xA5 -- 2.7.4