[PATCH v1] i2c: nuvoton: Add NPCM7xx i2c driver
Jim Liu
jim.t90615 at gmail.com
Tue May 24 05:05:35 CEST 2022
Hi Heiko
Thanks for your reply.
and i have some explanation about command check.
in the npcm_i2c_xfer, it can support 1 or 2 nmsgs so need for function .
the test as below:
---------------------------
U-Boot>i2c probe 0x50
Valid chip addresses:nmsgs= 1
50
U-Boot>i2c md 50 11.2 4
nmsgs= 2
0011: 12 13 14 15 ....
U-Boot>i2c mw 50 11.2 11
nmsgs= 1
U-Boot>i2c md 50 11.2 4
nmsgs= 2
0011: 11 13 14 15 ....
U-Boot>
--------------------------------
If you have any questions please let me know.
On Mon, May 23, 2022 at 4:42 PM Heiko Schocher <hs at denx.de> wrote:
>
> Hello Jim,
>
> On 23.05.22 10:16, Jim Liu wrote:
> > Hi Heiko
> >
> > Thanks for your reply.
> > I will follow your suggestion to modify it for version 2.
> > and some explain and question as below:
> >
> > 1. while function will do the i2c recovery feature .
> > the function will break when toggle 27 times or SDA is high.
> >> + while (1) {
> >> + /* toggle SCL line */
> >> + writeb(SMBCST_TGSCL, ®->cst);
> >> +
> >> + udelay(20);
> >> + val = readb(®->ctl3);
> >> + if (val & SMBCTL3_SDA_LVL)
> >> + break;
> >> + if (iter-- == 0)
> >> + break;
> >> + }
>
> Ah, yes, seems I was blind... sorry.
>
> > 2. npcm845 is our new bmc and we are on-going to push it to linux.
> > This link is our push status.
> > https://patchwork.ozlabs.org/project/linux-i2c/patch/20220517101142.28421-10-warp5tw@gmail.com/
>
> Ah, thanks!
>
> > may i keep this npcm845 compatible or remove it?
>
> If it gets accepted in linux, I am fine with it... ah I see:
>
> https://lore.kernel.org/lkml/20220517101142.28421-2-warp5tw@gmail.com/
>
> you add there the new compatible entry and have already a Reviewed-by
> from Rob, so I think this is fine to accept it in u-boot too.
>
> bye,
> Heiko
>
> > On Thu, May 19, 2022 at 12:48 PM Heiko Schocher <hs at denx.de> wrote:
> >>
> >> Hello Jim,
> >>
> >> On 17.05.22 10:25, Jim Liu wrote:
> >>> Add Nuvoton BMC NPCM750 i2c driver
> >>>
> >>> Signed-off-by: Jim Liu <JJLIU0 at nuvoton.com>
> >>> ---
> >>> drivers/i2c/Kconfig | 5 +
> >>> drivers/i2c/Makefile | 1 +
> >>> drivers/i2c/npcm-i2c.c | 632 +++++++++++++++++++++++++++++++++++++++++
> >>> 3 files changed, 638 insertions(+)
> >>> create mode 100644 drivers/i2c/npcm-i2c.c
> >>>
> >>> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
> >>> index d25c5736ef..7e113b289e 100644
> >>> --- a/drivers/i2c/Kconfig
> >>> +++ b/drivers/i2c/Kconfig
> >>> @@ -447,6 +447,11 @@ config SYS_I2C_NEXELL
> >>> have several I2C ports and all are provided, controlled by the
> >>> device tree.
> >>>
> >>> +config SYS_I2C_NPCM
> >>> + bool "Nuvoton NPCM I2C driver"
> >>> + help
> >>> + Support for Nuvoton I2C controller driver.
> >>> +
> >>> config SYS_I2C_OCORES
> >>> bool "ocores I2C driver"
> >>> depends on DM_I2C
> >>> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> >>> index 9d41f379bb..7e046f809a 100644
> >>> --- a/drivers/i2c/Makefile
> >>> +++ b/drivers/i2c/Makefile
> >>> @@ -33,6 +33,7 @@ obj-$(CONFIG_SYS_I2C_MV) += mv_i2c.o
> >>> obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
> >>> obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
> >>> obj-$(CONFIG_SYS_I2C_NEXELL) += nx_i2c.o
> >>> +obj-$(CONFIG_SYS_I2C_NPCM) += npcm_i2c.o
> >>> obj-$(CONFIG_SYS_I2C_OCORES) += ocores_i2c.o
> >>> obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
> >>> obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
> >>> diff --git a/drivers/i2c/npcm-i2c.c b/drivers/i2c/npcm-i2c.c
> >>> new file mode 100644
> >>> index 0000000000..5a066a164b
> >>> --- /dev/null
> >>> +++ b/drivers/i2c/npcm-i2c.c
> >>> @@ -0,0 +1,632 @@
> >>> +// SPDX-License-Identifier: GPL-2.0+
> >>> +/*
> >>> + * Copyright (c) 2021 Nuvoton Technology Corp.
> >>> + */
> >>> +
> >>> +#include <clk.h>
> >>> +#include <dm.h>
> >>> +#include <i2c.h>
> >>> +#include <asm/io.h>
> >>> +#include <linux/iopoll.h>
> >>> +#include <asm/arch/gcr.h>
> >>> +
> >>> +#define I2C_FREQ_100K 100000
> >>> +#define NPCM_I2C_TIMEOUT_MS 10
> >>> +#define NPCM7XX_I2CSEGCTL_INIT_VAL 0x0333F000
> >>> +#define NPCM8XX_I2CSEGCTL_INIT_VAL 0x9333F000
> >>> +
> >>> +/* SCLFRQ min/max field values */
> >>> +#define SCLFRQ_MIN 10
> >>> +#define SCLFRQ_MAX 511
> >>> +
> >>> +/* SMBCTL1 */
> >>> +#define SMBCTL1_START BIT(0)
> >>> +#define SMBCTL1_STOP BIT(1)
> >>> +#define SMBCTL1_INTEN BIT(2)
> >>> +#define SMBCTL1_ACK BIT(4)
> >>> +#define SMBCTL1_STASTRE BIT(7)
> >>> +
> >>> +/* SMBCTL2 */
> >>> +#define SMBCTL2_ENABLE BIT(0)
> >>> +
> >>> +/* SMBCTL3 */
> >>> +#define SMBCTL3_SCL_LVL BIT(7)
> >>> +#define SMBCTL3_SDA_LVL BIT(6)
> >>> +
> >>> +/* SMBCST */
> >>> +#define SMBCST_BB BIT(1)
> >>> +#define SMBCST_TGSCL BIT(5)
> >>> +
> >>> +/* SMBST */
> >>> +#define SMBST_XMIT BIT(0)
> >>> +#define SMBST_MASTER BIT(1)
> >>> +#define SMBST_STASTR BIT(3)
> >>> +#define SMBST_NEGACK BIT(4)
> >>> +#define SMBST_BER BIT(5)
> >>> +#define SMBST_SDAST BIT(6)
> >>> +
> >>> +/* SMBCST3 in bank0 */
> >>> +#define SMBCST3_EO_BUSY BIT(7)
> >>> +
> >>> +/* SMBFIF_CTS in bank1 */
> >>> +#define SMBFIF_CTS_CLR_FIFO BIT(6)
> >>> +
> >>> +#define SMBFIF_CTL_FIFO_EN BIT(4)
> >>> +#define SMBCTL3_BNK_SEL BIT(5)
> >>> +
> >>> +enum {
> >>> + I2C_ERR_NACK = 1,
> >>> + I2C_ERR_BER,
> >>> + I2C_ERR_TIMEOUT,
> >>> +};
> >>> +
> >>> +struct smb_bank0_regs {
> >>> + u8 addr3;
> >>> + u8 addr7;
> >>> + u8 addr4;
> >>> + u8 addr8;
> >>> + u16 addr5;
> >>> + u16 addr6;
> >>> + u8 cst2;
> >>> + u8 cst3;
> >>> + u8 ctl4;
> >>> + u8 ctl5;
> >>> + u8 scllt;
> >>> + u8 fif_ctl;
> >>> + u8 sclht;
> >>> +};
> >>> +
> >>> +struct smb_bank1_regs {
> >>> + u8 fif_cts;
> >>> + u8 fair_per;
> >>> + u16 txf_ctl;
> >>> + u32 t_out;
> >>> + u8 cst2;
> >>> + u8 cst3;
> >>> + u16 txf_sts;
> >>> + u16 rxf_sts;
> >>> + u8 rxf_ctl;
> >>> +};
> >>> +
> >>> +struct npcm_i2c_regs {
> >>> + u16 sda;
> >>> + u16 st;
> >>> + u16 cst;
> >>> + u16 ctl1;
> >>> + u16 addr;
> >>> + u16 ctl2;
> >>> + u16 addr2;
> >>> + u16 ctl3;
> >>> + union {
> >>> + struct smb_bank0_regs bank0;
> >>> + struct smb_bank1_regs bank1;
> >>> + };
> >>> +
> >>> +};
> >>> +
> >>> +struct npcm_i2c_bus {
> >>> + struct npcm_i2c_regs *reg;
> >>> + int num;
> >>> + u32 apb_clk;
> >>> + u32 freq;
> >>> + bool started;
> >>> +};
> >>> +
> >>> +static void npcm_dump_regs(struct npcm_i2c_bus *bus)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> +
> >>> + printf("\n");
> >>> + printf("SMBST=0x%x\n", readb(®->st));
> >>> + printf("SMBCST=0x%x\n", readb(®->cst));
> >>> + printf("SMBCTL1=0x%x\n", readb(®->ctl1));
> >>> + printf("\n");
> >>> +}
> >>> +
> >>> +static int npcm_i2c_check_sda(struct npcm_i2c_bus *bus)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + ulong start_time;
> >>> + int err = I2C_ERR_TIMEOUT;
> >>> + u8 val;
> >>> +
> >>> + start_time = get_timer(0);
> >>> + /* wait SDAST to be 1 */
> >>> + while (get_timer(start_time) < NPCM_I2C_TIMEOUT_MS) {
> >>> + val = readb(®->st);
> >>> + if (val & SMBST_NEGACK) {
> >>> + err = I2C_ERR_NACK;
> >>> + break;
> >>> + }
> >>> + if (val & SMBST_BER) {
> >>> + err = I2C_ERR_BER;
> >>> + break;
> >>> + }
> >>> + if (val & SMBST_SDAST) {
> >>> + err = 0;
> >>> + break;
> >>> + }
> >>> + }
> >>> +
> >>> + if (err)
> >>> + printf("%s: err %d\n", __func__, err);
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_send_start(struct npcm_i2c_bus *bus)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + ulong start_time;
> >>> + int err = I2C_ERR_TIMEOUT;
> >>> +
> >>> + /* Generate START condition */
> >>> + writeb(readb(®->ctl1) | SMBCTL1_START, ®->ctl1);
> >>> +
> >>> + start_time = get_timer(0);
> >>> + while (get_timer(start_time) < NPCM_I2C_TIMEOUT_MS) {
> >>> + if (readb(®->st) & SMBST_BER)
> >>> + return I2C_ERR_BER;
> >>> + if (readb(®->st) & SMBST_MASTER) {
> >>> + err = 0;
> >>> + break;
> >>> + }
> >>> + }
> >>> + bus->started = true;
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_send_stop(struct npcm_i2c_bus *bus, bool wait)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + ulong start_time;
> >>> + int err = I2C_ERR_TIMEOUT;
> >>> +
> >>> + writeb(readb(®->ctl1) | SMBCTL1_STOP, ®->ctl1);
> >>> +
> >>> + /* Clear NEGACK, STASTR and BER bits */
> >>> + writeb(SMBST_STASTR | SMBST_NEGACK | SMBST_BER, ®->st);
> >>> +
> >>> + bus->started = false;
> >>> +
> >>> + if (!wait)
> >>> + return 0;
> >>> +
> >>> + start_time = get_timer(0);
> >>> + while (get_timer(start_time) < NPCM_I2C_TIMEOUT_MS) {
> >>> + if ((readb(®->ctl1) & SMBCTL1_STOP) == 0) {
> >>> + err = 0;
> >>> + break;
> >>> + }
> >>> + }
> >>> + if (err) {
> >>> + printf("%s: err %d\n", __func__, err);
> >>> + npcm_dump_regs(bus);
> >>> + }
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static void npcm_i2c_reset(struct npcm_i2c_bus *bus)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> +
> >>> + printf("%s: module %d\n", __func__, bus->num);
> >>
> >> May better only debug() ?
> >>
> >>> + /* disable & enable SMB moudle */
> >>> + writeb(readb(®->ctl2) & ~SMBCTL2_ENABLE, ®->ctl2);
> >>> + writeb(readb(®->ctl2) | SMBCTL2_ENABLE, ®->ctl2);
> >>
> >> You may want to use here clr/setbits_8 and friends?
> >>
> >> Please use them in this driver, thanks!
> >>
> >>> +
> >>> + /* clear BB and status */
> >>> + writeb(SMBCST_BB, ®->cst);
> >>> + writeb(0xff, ®->st);
> >>> +
> >>> + /* select bank 1 */
> >>> + writeb(readb(®->ctl3) | SMBCTL3_BNK_SEL, ®->ctl3);
> >>> + /* Clear all fifo bits */
> >>> + writeb(SMBFIF_CTS_CLR_FIFO, ®->bank1.fif_cts);
> >>> +
> >>> + /* select bank 0 */
> >>> + writeb(readb(®->ctl3) & ~SMBCTL3_BNK_SEL, ®->ctl3);
> >>> + /* clear EOB bit */
> >>> + writeb(SMBCST3_EO_BUSY, ®->bank0.cst3);
> >>> + /* single byte mode */
> >>> + writeb(readb(®->bank0.fif_ctl) & ~SMBFIF_CTL_FIFO_EN, ®->bank0.fif_ctl);
> >>> +
> >>> + /* set POLL mode */
> >>> + writeb(0, ®->ctl1);
> >>> +}
> >>> +
> >>> +static void npcm_i2c_recovery(struct npcm_i2c_bus *bus, u32 addr)
> >>> +{
> >>> + u8 val;
> >>> + int iter = 27;
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + int err;
> >>> +
> >>> + val = readb(®->ctl3);
> >>> + /* Skip recovery, bus not stucked */
> >>> + if ((val & SMBCTL3_SCL_LVL) && (val & SMBCTL3_SDA_LVL))
> >>> + return;
> >>> +
> >>> + printf("Performing I2C bus %d recovery...\n", bus->num);
> >>> + /* SCL/SDA are not releaed, perform recovery */
> >>> + while (1) {
> >>> + /* toggle SCL line */
> >>> + writeb(SMBCST_TGSCL, ®->cst);
> >>> +
> >>> + udelay(20);
> >>> + val = readb(®->ctl3);
> >>> + if (val & SMBCTL3_SDA_LVL)
> >>> + break;
> >>> + if (iter-- == 0)
> >>> + break;
> >>> + }
> >>
> >> Hmm... endless while(1) ?
> >>
> >>> +
> >>> + if (val & SMBCTL3_SDA_LVL) {
> >>> + writeb((u8)((addr << 1) & 0xff), ®->sda);
> >>> + err = npcm_i2c_send_start(bus);
> >>> + if (!err) {
> >>> + udelay(20);
> >>> + npcm_i2c_send_stop(bus, false);
> >>> + udelay(200);
> >>> + printf("I2C bus %d recovery completed\n",
> >>> + bus->num);
> >>> + } else {
> >>> + printf("%s: send START err %d\n", __func__, err);
> >>> + }
> >>> + } else {
> >>> + printf("Fail to recover I2C bus %d\n", bus->num);
> >>> + }
> >>> + npcm_i2c_reset(bus);
> >>> +}
> >>> +
> >>> +static int npcm_i2c_send_address(struct npcm_i2c_bus *bus, u8 addr,
> >>> + bool stall)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + ulong start_time;
> >>> + u8 val;
> >>> +
> >>> + /* Stall After Start Enable */
> >>> + if (stall)
> >>> + writeb(readb(®->ctl1) | SMBCTL1_STASTRE, ®->ctl1);
> >>> +
> >>> + writeb(addr, ®->sda);
> >>> + if (stall) {
> >>> + start_time = get_timer(0);
> >>> + while (get_timer(start_time) < NPCM_I2C_TIMEOUT_MS) {
> >>> + if (readb(®->st) & SMBST_STASTR)
> >>> + break;
> >>> +
> >>> + if (readb(®->st) & SMBST_BER) {
> >>> + writeb(readb(®->ctl1) & ~SMBCTL1_STASTRE,
> >>> + ®->ctl1);
> >>> + return I2C_ERR_BER;
> >>> + }
> >>> + }
> >>> + }
> >>> +
> >>> + /* check ACK */
> >>> + val = readb(®->st);
> >>> + if (val & SMBST_NEGACK) {
> >>> + debug("NACK on addr 0x%x\n", addr >> 1);
> >>> + /* After a Stop condition, writing 1 to NEGACK clears it */
> >>> + return I2C_ERR_NACK;
> >>> + }
> >>> + if (val & SMBST_BER)
> >>> + return I2C_ERR_BER;
> >>> +
> >>> + return 0;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_read_bytes(struct npcm_i2c_bus *bus, u8 *data, int len)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + u8 val;
> >>> + int i;
> >>> + int err = 0;
> >>> +
> >>> + if (len == 1) {
> >>> + /* bus should be stalled before receiving last byte */
> >>> + writeb(readb(®->ctl1) | SMBCTL1_ACK, ®->ctl1);
> >>> +
> >>> + /* clear STASTRE if it is set */
> >>> + if (readb(®->ctl1) & SMBCTL1_STASTRE) {
> >>> + writeb(SMBST_STASTR, ®->st);
> >>> + writeb(readb(®->ctl1) & ~SMBCTL1_STASTRE, ®->ctl1);
> >>> + }
> >>> + npcm_i2c_check_sda(bus);
> >>> + npcm_i2c_send_stop(bus, false);
> >>> + *data = readb(®->sda);
> >>> + /* this must be done to generate STOP condition */
> >>> + writeb(SMBST_NEGACK, ®->st);
> >>> + } else {
> >>> + for (i = 0; i < len; i++) {
> >>> + /*
> >>> + * When NEGACK bit is set to 1 after the transmission of a byte,
> >>> + * SDAST is not set to 1.
> >>> + */
> >>> + if (i != (len - 1)) {
> >>> + err = npcm_i2c_check_sda(bus);
> >>> + } else {
> >>> + err = readb_poll_timeout(®->ctl1, val,
> >>> + !(val & SMBCTL1_ACK), 100000);
> >>> + if (err) {
> >>> + printf("wait nack timeout\n");
> >>> + err = I2C_ERR_TIMEOUT;
> >>> + npcm_dump_regs(bus);
> >>> + }
> >>> + }
> >>> + if (err && err != I2C_ERR_TIMEOUT)
> >>> + break;
> >>> + if (i == (len - 2)) {
> >>> + /* set NACK before last byte */
> >>> + writeb(readb(®->ctl1) | SMBCTL1_ACK, ®->ctl1);
> >>> + }
> >>> + if (i == (len - 1)) {
> >>> + /* last byte, send STOP condition */
> >>> + npcm_i2c_send_stop(bus, false);
> >>> + *data = readb(®->sda);
> >>> + writeb(SMBST_NEGACK, ®->st);
> >>> + break;
> >>> + }
> >>> + *data = readb(®->sda);
> >>> + data++;
> >>> + }
> >>> + }
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_send_bytes(struct npcm_i2c_bus *bus, u8 *data, int len)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + u8 val;
> >>> + int i;
> >>> + int err = 0;
> >>> +
> >>> + val = readb(®->st);
> >>> + if (val & SMBST_NEGACK)
> >>> + return I2C_ERR_NACK;
> >>> + else if (val & SMBST_BER)
> >>> + return I2C_ERR_BER;
> >>> +
> >>> + /* clear STASTRE if it is set */
> >>> + if (readb(®->ctl1) & SMBCTL1_STASTRE)
> >>> + writeb(readb(®->ctl1) & ~SMBCTL1_STASTRE, ®->ctl1);
> >>> +
> >>> + for (i = 0; i < len; i++) {
> >>> + err = npcm_i2c_check_sda(bus);
> >>> + if (err)
> >>> + break;
> >>> + writeb(*data, ®->sda);
> >>> + data++;
> >>> + }
> >>> + npcm_i2c_check_sda(bus);
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_read(struct npcm_i2c_bus *bus, u32 addr, u8 *data,
> >>> + u32 len)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + int err;
> >>> + bool stall;
> >>> +
> >>> + if (len <= 0)
> >>> + return -EINVAL;
> >>> +
> >>> + /* send START condition */
> >>> + err = npcm_i2c_send_start(bus);
> >>> + if (err) {
> >>> + debug("%s: send START err %d\n", __func__, err);
> >>> + return err;
> >>> + }
> >>> +
> >>> + stall = (len == 1) ? true : false;
> >>> + /* send address byte */
> >>> + err = npcm_i2c_send_address(bus, (u8)(addr << 1) | 0x1, stall);
> >>> +
> >>> + if (!err && len)
> >>> + npcm_i2c_read_bytes(bus, data, len);
> >>> +
> >>> + if (err == I2C_ERR_NACK) {
> >>> + /* clear NACK */
> >>> + writeb(SMBST_NEGACK, ®->st);
> >>> + }
> >>> +
> >>> + if (err)
> >>> + debug("%s: err %d\n", __func__, err);
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_write(struct npcm_i2c_bus *bus, u32 addr, u8 *data,
> >>> + u32 len)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + int err;
> >>> + bool stall;
> >>> +
> >>> + /* send START condition */
> >>> + err = npcm_i2c_send_start(bus);
> >>> + if (err) {
> >>> + debug("%s: send START err %d\n", __func__, err);
> >>> + return err;
> >>> + }
> >>> +
> >>> + stall = (len == 0) ? true : false;
> >>> + /* send address byte */
> >>> + err = npcm_i2c_send_address(bus, (u8)(addr << 1), stall);
> >>> +
> >>> + if (!err && len)
> >>> + err = npcm_i2c_send_bytes(bus, data, len);
> >>> +
> >>> + /* clear STASTRE if it is set */
> >>> + if (stall)
> >>> + writeb(readb(®->ctl1) & ~SMBCTL1_STASTRE, ®->ctl1);
> >>> +
> >>> + if (err)
> >>> + debug("%s: err %d\n", __func__, err);
> >>> +
> >>> + return err;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_xfer(struct udevice *dev,
> >>> + struct i2c_msg *msg, int nmsgs)
> >>> +{
> >>> + struct npcm_i2c_bus *bus = dev_get_priv(dev);
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + int ret = 0, err = 0;
> >>> +
> >>> + if (nmsgs < 1 || nmsgs > 2) {
> >>> + printf("%s: commands not support\n", __func__);
> >>> + return -EREMOTEIO;
> >>> + }
> >>> + /* clear ST register */
> >>> + writeb(0xFF, ®->st);
> >>> +
> >>> + for ( ; nmsgs > 0; nmsgs--, msg++) {
> >>
> >> above you say no commands supported, so this for loop is useless ..or?
> >>
> >>> + if (msg->flags & I2C_M_RD)
> >>> + err = npcm_i2c_read(bus, msg->addr, msg->buf,
> >>> + msg->len);
> >>> + else
> >>> + err = npcm_i2c_write(bus, msg->addr, msg->buf,
> >>> + msg->len);
> >>> + if (err) {
> >>> + debug("i2c_xfer: error %d\n", err);
> >>> + ret = -EREMOTEIO;
> >>> + break;
> >>> + }
> >>> + }
> >>> +
> >>> + if (bus->started)
> >>> + npcm_i2c_send_stop(bus, true);
> >>> +
> >>> + if (err)
> >>> + npcm_i2c_recovery(bus, msg->addr);
> >>> +
> >>> + return ret;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_init_clk(struct npcm_i2c_bus *bus, u32 bus_freq)
> >>> +{
> >>> + struct npcm_i2c_regs *reg = bus->reg;
> >>> + u32 freq = bus->apb_clk;
> >>> + u32 sclfrq;
> >>> + u8 hldt, val;
> >>> +
> >>> + if (bus_freq > I2C_FREQ_100K) {
> >>> + printf("Support standard mode only\n");
> >>> + return -EINVAL;
> >>> + }
> >>> +
> >>> + /* SCLFRQ = T(SCL)/4/T(CLK) = FREQ(CLK)/4/FREQ(SCL) */
> >>> + sclfrq = freq / (bus_freq * 4);
> >>> + if (sclfrq < SCLFRQ_MIN || sclfrq > SCLFRQ_MAX)
> >>> + return -EINVAL;
> >>> +
> >>> + if (freq >= 40000000)
> >>> + hldt = 17;
> >>> + else if (freq >= 12500000)
> >>> + hldt = 15;
> >>> + else
> >>> + hldt = 7;
> >>> +
> >>> + val = readb(®->ctl2) & 0x1;
> >>> + val |= (sclfrq & 0x7F) << 1;
> >>> + writeb(val, ®->ctl2);
> >>> +
> >>> + /* clear 400K_MODE bit */
> >>> + val = readb(®->ctl3) & 0xc;
> >>> + val |= (sclfrq >> 7) & 0x3;
> >>> + writeb(val, ®->ctl3);
> >>> +
> >>> + writeb(hldt, ®->bank0.ctl4);
> >>> +
> >>> + return 0;
> >>> +}
> >>> +
> >>> +static int npcm_i2c_set_bus_speed(struct udevice *dev,
> >>> + unsigned int speed)
> >>> +{
> >>> + struct npcm_i2c_bus *bus = dev_get_priv(dev);
> >>> +
> >>> + return npcm_i2c_init_clk(bus, speed);
> >>> +}
> >>> +
> >>> +static int npcm_i2c_probe(struct udevice *dev)
> >>> +{
> >>> + struct npcm_i2c_bus *bus = dev_get_priv(dev);
> >>> + struct npcm_gcr *gcr = (struct npcm_gcr *)NPCM_GCR_BA;
> >>> + struct npcm_i2c_regs *reg;
> >>> + u32 i2csegctl_val = dev_get_driver_data(dev);
> >>> + struct clk clk;
> >>> + int ret;
> >>> +
> >>> + ret = clk_get_by_index(dev, 0, &clk);
> >>> + if (ret) {
> >>> + printf("%s: ret %d\n", __func__, ret);
> >>> + return ret;
> >>> + }
> >>> + bus->apb_clk = clk_get_rate(&clk);
> >>> + if (bus->apb_clk <= 0) {
> >>> + printf("%s: fail to get rate\n", __func__);
> >>> + return -EINVAL;
> >>> + }
> >>> + clk_free(&clk);
> >>> +
> >>> + bus->num = dev->seq_;
> >>> + bus->reg = dev_read_addr_ptr(dev);
> >>> + bus->freq = dev_read_u32_default(dev, "clock-frequency", 100000);
> >>> + bus->started = false;
> >>> + reg = bus->reg;
> >>> +
> >>> + if (npcm_i2c_init_clk(bus, bus->freq)) {
> >>> + printf("%s: init_clk failed\n", __func__);
> >>> + return -EINVAL;
> >>> + }
> >>> +
> >>> + /* set initial i2csegctl value */
> >>> + writel(i2csegctl_val, &gcr->i2csegctl);
> >>> +
> >>> + /* enable SMB module */
> >>> + writeb(readb(®->ctl2) | SMBCTL2_ENABLE, ®->ctl2);
> >>> +
> >>> + /* select register bank 0 */
> >>> + writeb(readb(®->ctl3) & ~SMBCTL3_BNK_SEL, ®->ctl3);
> >>> +
> >>> + /* single byte mode */
> >>> + writeb(readb(®->bank0.fif_ctl) & ~SMBFIF_CTL_FIFO_EN, ®->bank0.fif_ctl);
> >>> +
> >>> + /* set POLL mode */
> >>> + writeb(0, ®->ctl1);
> >>> +
> >>> + printf("I2C bus %d ready. speed=%d, base=0x%x, apb=%u\n",
> >>> + bus->num, bus->freq, (u32)(uintptr_t)bus->reg, bus->apb_clk);
> >>
> >> Please use debug here.
> >>
> >>> +
> >>> + return 0;
> >>> +}
> >>> +
> >>> +static const struct dm_i2c_ops nuvoton_i2c_ops = {
> >>> + .xfer = npcm_i2c_xfer,
> >>> + .set_bus_speed = npcm_i2c_set_bus_speed,
> >>> +};
> >>
> >> As you have a deblock function, may you want to set
> >> .deblock here too?
> >>
> >>> +
> >>> +static const struct udevice_id nuvoton_i2c_of_match[] = {
> >>> + { .compatible = "nuvoton,npcm845-i2c", .data = NPCM8XX_I2CSEGCTL_INIT_VAL},
> >>
> >> I do not find this string in linux ... do you plan to push this
> >> to linux?
> >>
> >>> + { .compatible = "nuvoton,npcm750-i2c", .data = NPCM7XX_I2CSEGCTL_INIT_VAL},
> >>> + {}
> >>> +};
> >>
> >> and please document the bindings in u-boot:/doc/device-tree-bindings/i2c
> >>
> >>> +
> >>> +U_BOOT_DRIVER(npcm_i2c_bus) = {
> >>> + .name = "npcm-i2c",
> >>> + .id = UCLASS_I2C,
> >>> + .of_match = nuvoton_i2c_of_match,
> >>> + .probe = npcm_i2c_probe,
> >>> + .priv_auto = sizeof(struct npcm_i2c_bus),
> >>> + .ops = &nuvoton_i2c_ops,
> >>> +};
> >>> +
> >>>
> >>
> >> Thanks!
> >>
> >> bye,
> >> Heiko
> >> --
> >> DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
> >> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> >> Phone: +49-8142-66989-52 Fax: +49-8142-66989-80 Email: hs at denx.de
>
> --
> DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: +49-8142-66989-52 Fax: +49-8142-66989-80 Email: hs at denx.de
More information about the U-Boot
mailing list