[PATCH v10 2/2] i2c: aspeed: support ast2600 i2c new register mode driver
Christophe JAILLET
christophe.jaillet at wanadoo.fr
Sat Apr 15 03:05:47 PDT 2023
(resending, my mail client removed some addresses. Sorry for the
duplicated message for the others)
Le 15/04/2023 à 03:28, Ryan Chen a écrit :
> Add i2c new register mode driver to support AST2600 i2c
> new register mode. AST2600 i2c controller have legacy and
> new register mode. The new register mode have global register
> support 4 base clock for scl clock selection, and new clock
> divider mode. The i2c new register mode have separate register
> set to control i2c master and slave.
>
> Signed-off-by: Ryan Chen <ryan_chen at aspeedtech.com>
> ---
[...]
> +static u8 ast2600_i2c_recover_bus(struct ast2600_i2c_bus *i2c_bus)
> +{
> + int ret = 0;
> + u32 ctrl;
> + u32 state;
> + int r;
> +
> + dev_dbg(i2c_bus->dev, "%d-bus recovery bus [%x]\n",
i2c_bus->adap.nr,
> + readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> +
> + ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> + writel(ctrl & ~(AST2600_I2CC_MASTER_EN | AST2600_I2CC_SLAVE_EN),
> + i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> + writel(readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) |
AST2600_I2CC_MASTER_EN,
> + i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> + reinit_completion(&i2c_bus->cmd_complete);
> + i2c_bus->cmd_err = 0;
> +
> + /* Check 0x14's SDA and SCL status */
> + state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
> + if (!(state & AST2600_I2CC_SDA_LINE_STS) && (state &
AST2600_I2CC_SCL_LINE_STS)) {
> + writel(AST2600_I2CM_RECOVER_CMD_EN, i2c_bus->reg_base +
AST2600_I2CM_CMD_STS);
> + r = wait_for_completion_timeout(&i2c_bus->cmd_complete,
i2c_bus->adap.timeout);
> + if (r == 0) {
> + dev_dbg(i2c_bus->dev, "recovery timed out\n");
> + ret = -ETIMEDOUT;
> + } else {
> + if (i2c_bus->cmd_err) {
> + dev_dbg(i2c_bus->dev, "recovery error\n");
> + ret = -EPROTO;
> + }
> + }
> + }
> +
> + dev_dbg(i2c_bus->dev, "Recovery done [%x]\n",
> + readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> + if (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
AST2600_I2CC_BUS_BUSY_STS) {
> + dev_dbg(i2c_bus->dev, "Can't recovery bus [%x]\n",
recover?
> + readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> + ret = -EPROTO;
> + }
> +
> + writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> + return ret;
> +}
> +
> +#ifdef CONFIG_I2C_SLAVE
> +static void ast2600_i2c_slave_packet_dma_irq(struct ast2600_i2c_bus
*i2c_bus, u32 sts)
> +{
> + int slave_rx_len;
> + u32 cmd = 0;
> + u8 value;
> + int i = 0;
No need to init
> +
> + sts &= ~(AST2600_I2CS_SLAVE_PENDING);
> + /* Handle i2c slave timeout condition */
> + if (AST2600_I2CS_INACTIVE_TO & sts) {
> + cmd = SLAVE_TRIGGER_CMD;
> + cmd |= AST2600_I2CS_RX_DMA_EN;
> + writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
AST2600_I2CS_ISR);
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + return;
> + }
> +
> + sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
> +
> + switch (sts) {
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_WAIT_RX_DMA:
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
&value);
> + slave_rx_len =
AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CS_DMA_LEN_STS));
> + for (i = 0; i < slave_rx_len; i++) {
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
> + &i2c_bus->slave_dma_buf[i]);
> + }
> + writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> + break;
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> + break;
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE_NAK |
> + AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA |
> + AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> + case AST2600_I2CS_RX_DONE_NAK | AST2600_I2CS_RX_DONE |
AST2600_I2CS_STOP:
> + case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA |
AST2600_I2CS_STOP:
> + case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> + case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_STOP:
> + if (sts & AST2600_I2CS_SLAVE_MATCH)
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_REQUESTED, &value);
> +
> + slave_rx_len =
AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CS_DMA_LEN_STS));
> + for (i = 0; i < slave_rx_len; i++) {
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
> + &i2c_bus->slave_dma_buf[i]);
> + }
> + writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + if (sts & AST2600_I2CS_STOP)
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> + break;
> +
> + /* it is Mw data Mr coming -> it need send tx */
> + case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_WAIT_TX_DMA:
> + /* it should be repeat start read */
> + if (sts & AST2600_I2CS_SLAVE_MATCH)
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_REQUESTED, &value);
> +
> + slave_rx_len =
AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CS_DMA_LEN_STS));
> + for (i = 0; i < slave_rx_len; i++) {
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
> + &i2c_bus->slave_dma_buf[i]);
> + }
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
> + &i2c_bus->slave_dma_buf[0]);
> + writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
> + writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
> + break;
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_TX_DMA:
> + /* First Start read */
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
> + &i2c_bus->slave_dma_buf[0]);
> + writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
> + break;
> + case AST2600_I2CS_WAIT_TX_DMA:
> + /* it should be next start read */
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED,
> + &i2c_bus->slave_dma_buf[0]);
> + writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
> + writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
> + break;
Having a new line or not after breaks is not consistent.
> +
> + case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
> + /* it just tx complete */
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
> + writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> + break;
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
> + cmd = 0;
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
&value);
> + break;
> + case AST2600_I2CS_STOP:
> + cmd = 0;
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + break;
> + default:
> + dev_dbg(i2c_bus->dev, "unhandled slave isr case %x, sts
%x\n", sts,
> + readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> + break;
> + }
> +
> + if (cmd)
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
> + readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +}
> +
> +static void ast2600_i2c_slave_packet_buff_irq(struct ast2600_i2c_bus
*i2c_bus, u32 sts)
> +{
> + int slave_rx_len = 0;
> + u32 cmd = 0;
> + u8 value;
> + int i = 0;
No need to init;
> +
> + /* due to master slave is common buffer, so need force the
master stop not issue */
> + if (readl(i2c_bus->reg_base + AST2600_I2CM_CMD_STS) & 0xffff) {
> + writel(0, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
> + i2c_bus->cmd_err = -EBUSY;
> + writel(0, i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + complete(&i2c_bus->cmd_complete);
> + }
> +
> + /* Handle i2c slave timeout condition */
> + if (AST2600_I2CS_INACTIVE_TO & sts) {
> + writel(SLAVE_TRIGGER_CMD, i2c_bus->reg_base +
AST2600_I2CS_CMD_STS);
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
AST2600_I2CS_ISR);
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + i2c_bus->slave_operate = 0;
> + return;
> + }
> +
> + sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
> +
> + if (sts & AST2600_I2CS_SLAVE_MATCH)
> + i2c_bus->slave_operate = 1;
> +
> + switch (sts) {
> + case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
> + AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_STOP:
> + case AST2600_I2CS_SLAVE_PENDING |
> + AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_STOP:
> + case AST2600_I2CS_SLAVE_PENDING |
> + AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + fallthrough;
> + case AST2600_I2CS_SLAVE_PENDING |
> + AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH |
AST2600_I2CS_RX_DONE:
> + case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH |
AST2600_I2CS_RX_DONE:
> + case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
&value);
> + cmd = SLAVE_TRIGGER_CMD;
> + if (sts & AST2600_I2CS_RX_DONE) {
> + slave_rx_len =
AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CC_BUFF_CTRL));
> + for (i = 0; i < slave_rx_len; i++) {
> + value = readb(i2c_bus->buf_base + 0x10 + i);
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED, &value);
> + }
> + }
> + if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) &
AST2600_I2CS_RX_BUFF_EN)
> + cmd = 0;
> + else
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
> +
> + writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
> + i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + break;
> + case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_RX_DONE:
> + cmd = SLAVE_TRIGGER_CMD;
> + slave_rx_len =
AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CC_BUFF_CTRL));
> + for (i = 0; i < slave_rx_len; i++) {
> + value = readb(i2c_bus->buf_base + 0x10 + i);
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED, &value);
> + }
> + cmd |= AST2600_I2CS_RX_BUFF_EN;
> + writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
> + i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + break;
> + case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
> + AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> + cmd = SLAVE_TRIGGER_CMD;
> + slave_rx_len =
AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CC_BUFF_CTRL));
> + for (i = 0; i < slave_rx_len; i++) {
> + value = readb(i2c_bus->buf_base + 0x10 + i);
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED, &value);
> + }
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + cmd |= AST2600_I2CS_RX_BUFF_EN;
> + writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
> + i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + break;
> +
Having a new line or not after breaks is not consistent.
> + case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_RX_DONE |
AST2600_I2CS_STOP:
> + cmd = SLAVE_TRIGGER_CMD;
> + slave_rx_len =
AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CC_BUFF_CTRL));
> + for (i = 0; i < slave_rx_len; i++) {
> + value = readb(i2c_bus->buf_base + 0x10 + i);
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED, &value);
> + }
> + /* workaround for avoid next start with len != 0 */
> + writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + break;
> +
> + case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> + cmd = SLAVE_TRIGGER_CMD;
> + slave_rx_len =
AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CC_BUFF_CTRL));
> + for (i = 0; i < slave_rx_len; i++) {
> + value = readb(i2c_bus->buf_base + 0x10 + i);
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED, &value);
> + }
> + /* workaround for avoid next start with len != 0 */
> + writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + break;
> + case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_SLAVE_MATCH:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
&value);
> + writeb(value, i2c_bus->buf_base);
> + writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
> + i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
> + break;
> + case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_RX_DONE:
> + case AST2600_I2CS_WAIT_TX_DMA:
> + if (sts & AST2600_I2CS_RX_DONE) {
> + slave_rx_len =
AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> + AST2600_I2CC_BUFF_CTRL));
> + for (i = 0; i < slave_rx_len; i++) {
> + value = readb(i2c_bus->buf_base + 0x10 + i);
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED, &value);
> + }
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_READ_REQUESTED, &value);
> + } else {
> + i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_READ_PROCESSED, &value);
> + }
> + writeb(value, i2c_bus->buf_base);
> + writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
> + i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
> + break;
> + /* workaround : trigger the cmd twice to fix next state keep
1000000 */
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
&value);
> + cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + break;
> +
> + case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
> + case AST2600_I2CS_STOP:
> + cmd = SLAVE_TRIGGER_CMD;
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + break;
> + default:
> + dev_dbg(i2c_bus->dev, "unhandled slave isr case %x, sts
%x\n", sts,
> + readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> + break;
> + }
> +
> + if (cmd)
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
> + readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +
> + if ((sts & AST2600_I2CS_STOP) && !(sts &
AST2600_I2CS_SLAVE_PENDING))
> + i2c_bus->slave_operate = 0;
> +
Nit: unneeded empty line.
> +}
> +
> +static void ast2600_i2c_slave_byte_irq(struct ast2600_i2c_bus
*i2c_bus, u32 sts)
> +{
> + u32 i2c_buff = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
> + u32 cmd = AST2600_I2CS_ACTIVE_ALL;
> + u8 byte_data;
> + u8 value;
> +
> + switch (sts) {
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_WAIT_RX_DMA:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
&value);
> + /* first address match is address */
> + byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
> + break;
> + case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
> + byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
&byte_data);
> + break;
> + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
AST2600_I2CS_WAIT_TX_DMA:
> + cmd |= AST2600_I2CS_TX_CMD;
> + byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
&byte_data);
> + writel(byte_data, i2c_bus->reg_base +
AST2600_I2CC_STS_AND_BUFF);
> + break;
> + case AST2600_I2CS_TX_ACK | AST2600_I2CS_WAIT_TX_DMA:
> + cmd |= AST2600_I2CS_TX_CMD;
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED,
&byte_data);
> + writel(byte_data, i2c_bus->reg_base +
AST2600_I2CC_STS_AND_BUFF);
> + break;
> + case AST2600_I2CS_STOP:
> + case AST2600_I2CS_STOP | AST2600_I2CS_TX_NAK:
> + i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> + break;
> + default:
> + dev_dbg(i2c_bus->dev, "unhandled pkt isr %x\n", sts);
> + break;
> + }
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + writel(sts, i2c_bus->reg_base + AST2600_I2CS_ISR);
> + readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +}
> +
> +static int ast2600_i2c_slave_irq(struct ast2600_i2c_bus *i2c_bus)
> +{
> + u32 ier = readl(i2c_bus->reg_base + AST2600_I2CS_IER);
> + u32 isr = readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +
> + if (!(isr & ier))
> + return 0;
> +
> + /* Slave interrupt coming after Master package done
> + * So need handle master first.
> + */
> + if (readl(i2c_bus->reg_base + AST2600_I2CM_ISR) &
AST2600_I2CM_PKT_DONE)
> + return 0;
> +
> + isr &= ~(AST2600_I2CS_ADDR_INDICATE_MASK);
> +
> + if (AST2600_I2CS_ADDR1_NAK & isr)
> + isr &= ~AST2600_I2CS_ADDR1_NAK;
> +
> + if (AST2600_I2CS_ADDR2_NAK & isr)
> + isr &= ~AST2600_I2CS_ADDR2_NAK;
> +
> + if (AST2600_I2CS_ADDR3_NAK & isr)
> + isr &= ~AST2600_I2CS_ADDR3_NAK;
> +
> + if (AST2600_I2CS_ADDR_MASK & isr)
> + isr &= ~AST2600_I2CS_ADDR_MASK;
> +
> + if (AST2600_I2CS_PKT_DONE & isr) {
> + if (i2c_bus->mode == DMA_MODE)
> + ast2600_i2c_slave_packet_dma_irq(i2c_bus, isr);
> + else
> + ast2600_i2c_slave_packet_buff_irq(i2c_bus, isr);
> + } else
> + ast2600_i2c_slave_byte_irq(i2c_bus, isr);
> +
> + return 1;
> +}
> +#endif
> +
> +static int ast2600_i2c_do_start(struct ast2600_i2c_bus *i2c_bus)
> +{
> + struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
> + int xfer_len = 0;
> + int i = 0;
No need to init.
> + u32 cmd;
> +
> + cmd = AST2600_I2CM_PKT_EN | AST2600_I2CM_PKT_ADDR(msg->addr) |
AST2600_I2CM_START_CMD;
> +
> + /* send start */
> + dev_dbg(i2c_bus->dev, "[%d] %sing %d byte%s %s 0x%02x\n",
> + i2c_bus->msgs_index, msg->flags & I2C_M_RD ? "read" : "write",
> + msg->len, msg->len > 1 ? "s" : "",
> + msg->flags & I2C_M_RD ? "from" : "to", msg->addr);
> +
> + i2c_bus->master_xfer_cnt = 0;
> + i2c_bus->buf_index = 0;
[...]
> +static int ast2600_i2c_master_xfer(struct i2c_adapter *adap,
> + struct i2c_msg *msgs, int num)
> +{
> + struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(adap);
> + unsigned long timeout;
> + int ret = 0;
Looks like this initialization is unneeded.
> +
> + /* If bus is busy in a single master environment, attempt
recovery. */
> + if (!i2c_bus->multi_master &&
> + (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
AST2600_I2CC_BUS_BUSY_STS)) {
> + int ret;
No need for an extra 'ret'.
> +
> + ret = ast2600_i2c_recover_bus(i2c_bus);
> + if (ret)
> + return ret;
> + }
> +
> +#ifdef CONFIG_I2C_SLAVE
> + if (i2c_bus->mode == BUFF_MODE) {
> + if (i2c_bus->slave_operate)
> + return -EBUSY;
> + /* disable slave isr */
> + writel(0, i2c_bus->reg_base + AST2600_I2CS_IER);
> + if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR) ||
(i2c_bus->slave_operate)) {
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
AST2600_I2CS_IER);
> + return -EBUSY;
> + }
> + }
> +#endif
> +
> + i2c_bus->cmd_err = 0;
> + i2c_bus->msgs = msgs;
> + i2c_bus->msgs_index = 0;
> + i2c_bus->msgs_count = num;
> + reinit_completion(&i2c_bus->cmd_complete);
> + ret = ast2600_i2c_do_start(i2c_bus);
> +#ifdef CONFIG_I2C_SLAVE
> + /* avoid race condication slave is wait and master wait 1st
slave operate */
> + if (i2c_bus->mode == BUFF_MODE)
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
AST2600_I2CS_IER);
> +#endif
> + if (ret)
> + goto master_out;
> + timeout = wait_for_completion_timeout(&i2c_bus->cmd_complete,
i2c_bus->adap.timeout);
> + if (timeout == 0) {
> + u32 isr = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
> + u32 i2c_status = readl(i2c_bus->reg_base +
AST2600_I2CC_STS_AND_BUFF);
> +
> + dev_dbg(i2c_bus->dev, "timeout isr[%x], sts[%x]\n", isr,
i2c_status);
> + if (isr || (i2c_status & AST2600_I2CC_TX_DIR_MASK)) {
> + u32 ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> + writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> + writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +#ifdef CONFIG_I2C_SLAVE
> + if (ctrl & AST2600_I2CC_SLAVE_EN) {
> + u32 cmd = SLAVE_TRIGGER_CMD;
> +
> + if (i2c_bus->mode == DMA_MODE) {
> + cmd |= AST2600_I2CS_RX_DMA_EN;
> + writel(i2c_bus->slave_dma_addr,
> + i2c_bus->reg_base + AST2600_I2CS_RX_DMA);
> + writel(i2c_bus->slave_dma_addr,
> + i2c_bus->reg_base + AST2600_I2CS_TX_DMA);
> +
writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + } else if (i2c_bus->mode == BUFF_MODE) {
> + cmd = SLAVE_TRIGGER_CMD;
> + } else {
> + cmd &= ~AST2600_I2CS_PKT_MODE_EN;
> + }
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + }
> +#endif
> + }
> + ret = -ETIMEDOUT;
> + } else {
> + ret = i2c_bus->cmd_err;
> + }
> +
> + dev_dbg(i2c_bus->dev, "bus%d-m: %d end\n", i2c_bus->adap.nr,
i2c_bus->cmd_err);
> +
> +master_out:
> + if (i2c_bus->mode == DMA_MODE) {
> + kfree(i2c_bus->master_safe_buf);
> + i2c_bus->master_safe_buf = NULL;
Alignement.
> + }
> +
> + return ret;
> +}
> +
> +static void ast2600_i2c_init(struct ast2600_i2c_bus *i2c_bus)
> +{
> + struct platform_device *pdev = to_platform_device(i2c_bus->dev);
> + u32 fun_ctrl = AST2600_I2CC_BUS_AUTO_RELEASE |
AST2600_I2CC_MASTER_EN;
> +
> + /* I2C Reset */
> + writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> + if (of_property_read_bool(pdev->dev.of_node, "multi-master"))
> + i2c_bus->multi_master = true;
> + else
> + fun_ctrl |= AST2600_I2CC_MULTI_MASTER_DIS;
> +
> + /* Enable Master Mode */
> + writel(fun_ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> + /* disable slave address */
> + writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> +
> + /* Set AC Timing */
> + writel(ast2600_select_i2c_clock(i2c_bus), i2c_bus->reg_base +
AST2600_I2CC_AC_TIMING);
> +
> + /* Clear Interrupt */
> + writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CM_ISR);
> +
> +#ifdef CONFIG_I2C_SLAVE
> + /* for memory buffer initial */
> + if (i2c_bus->mode == DMA_MODE) {
> + i2c_bus->slave_dma_buf = dma_alloc_coherent(i2c_bus->dev,
I2C_SLAVE_MSG_BUF_SIZE,
> + &i2c_bus->slave_dma_addr, GFP_KERNEL);
dmam_alloc_coherent() could maybe be used here.
This would simplify the remove function and avoid some conditional
compilation.
This also fixes a leak if i2c_add_adapter() fails in the probe.
It is also likely that doing so, the devm_free_irq() in the remove
function also becomes redundant and can be removed as well.
> + if (!i2c_bus->slave_dma_buf)
> + return;
> + }
> +
> + writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CS_ISR);
> +
> + if (i2c_bus->mode == BYTE_MODE) {
> + writel(0xffff, i2c_bus->reg_base + AST2600_I2CS_IER);
> + } else {
> + /* Set interrupt generation of I2C slave controller */
> + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
AST2600_I2CS_IER);
> + }
> +#endif
> +}
> +
> +#ifdef CONFIG_I2C_SLAVE
> +static int ast2600_i2c_reg_slave(struct i2c_client *client)
> +{
> + struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(client->adapter);
> + u32 cmd = SLAVE_TRIGGER_CMD;
> +
> + if (i2c_bus->slave)
> + return -EINVAL;
> +
> + dev_dbg(i2c_bus->dev, "slave addr %x\n", client->addr);
> +
> + writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> + writel(AST2600_I2CC_SLAVE_EN | readl(i2c_bus->reg_base +
AST2600_I2CC_FUN_CTRL),
> + i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> + /* trigger rx buffer */
> + if (i2c_bus->mode == DMA_MODE) {
> + cmd |= AST2600_I2CS_RX_DMA_EN;
> + writel(i2c_bus->slave_dma_addr, i2c_bus->reg_base +
AST2600_I2CS_RX_DMA);
> + writel(i2c_bus->slave_dma_addr, i2c_bus->reg_base +
AST2600_I2CS_TX_DMA);
> + writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> + } else if (i2c_bus->mode == BUFF_MODE) {
> + cmd = SLAVE_TRIGGER_CMD;
> + } else {
> + cmd &= ~AST2600_I2CS_PKT_MODE_EN;
> + }
> +
> + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> + i2c_bus->slave = client;
> + /* Set slave addr. */
> + writel(client->addr | AST2600_I2CS_ADDR1_ENABLE,
> + i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
Nit: alignement
> +
> + return 0;
> +}
> +
> +static int ast2600_i2c_unreg_slave(struct i2c_client *slave)
> +{
> + struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(slave->adapter);
> +
> + WARN_ON(!i2c_bus->slave);
> +
> + /* Turn off slave mode. */
> + writel(~AST2600_I2CC_SLAVE_EN & readl(i2c_bus->reg_base +
AST2600_I2CC_FUN_CTRL),
> + i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> + writel(readl(i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL) &
~AST2600_I2CS_ADDR1_MASK,
> + i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> +
> + i2c_bus->slave = NULL;
> +
> + return 0;
> +}
> +#endif
> +
> +static u32 ast2600_i2c_functionality(struct i2c_adapter *adap)
> +{
> + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
I2C_FUNC_SMBUS_BLOCK_DATA;
> +}
> +
> +static const struct i2c_algorithm i2c_ast2600_algorithm = {
> + .master_xfer = ast2600_i2c_master_xfer,
> +#if IS_ENABLED(CONFIG_I2C_SLAVE)
> + .reg_slave = ast2600_i2c_reg_slave,
> + .unreg_slave = ast2600_i2c_unreg_slave,
> +#endif
> + .functionality = ast2600_i2c_functionality,
> +};
> +
> +static const struct of_device_id ast2600_i2c_bus_of_table[] = {
> + {
> + .compatible = "aspeed,ast2600-i2cv2",
> + },
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(of, ast2600_i2c_bus_of_table);
> +
> +static int ast2600_i2c_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct device *dev = &pdev->dev;
> + struct ast2600_i2c_bus *i2c_bus;
> + struct resource *res;
> + u32 global_ctrl;
> + int ret = 0;
> +
> + i2c_bus = devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL);
> + if (!i2c_bus)
> + return -ENOMEM;
> +
> + i2c_bus->reg_base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(i2c_bus->reg_base))
> + return PTR_ERR(i2c_bus->reg_base);
> +
> + i2c_bus->rst = devm_reset_control_get_shared(dev, NULL);
> + if (IS_ERR(i2c_bus->rst))
> + return dev_err_probe(dev, PTR_ERR(i2c_bus->rst), "Missing
reset ctrl\n");
> +
> + reset_control_deassert(i2c_bus->rst);
> +
> + i2c_bus->global_regs = syscon_regmap_lookup_by_phandle(np,
"aspeed,global-regs");
> + if (IS_ERR(i2c_bus->global_regs))
> + return PTR_ERR(i2c_bus->global_regs);
> +
> + regmap_read(i2c_bus->global_regs, AST2600_I2CG_CTRL, &global_ctrl);
> + if ((global_ctrl & AST2600_GLOBAL_INIT) != AST2600_GLOBAL_INIT) {
> + regmap_write(i2c_bus->global_regs, AST2600_I2CG_CTRL,
AST2600_GLOBAL_INIT);
> + regmap_write(i2c_bus->global_regs,
AST2600_I2CG_CLK_DIV_CTRL, I2CCG_DIV_CTRL);
> + }
> +
> + i2c_bus->slave_operate = 0;
> + i2c_bus->dev = dev;
> + i2c_bus->mode = BUFF_MODE;
> +
> + if (of_property_read_bool(pdev->dev.of_node, "aspeed,enable-dma"))
> + i2c_bus->mode = DMA_MODE;
> +
> + if (i2c_bus->mode == BUFF_MODE) {
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + if (res && resource_size(res) >= 2) {
> + i2c_bus->buf_base = devm_ioremap_resource(dev, res);
> +
> + if (!IS_ERR_OR_NULL(i2c_bus->buf_base))
> + i2c_bus->buf_size = resource_size(res)/2;
> + } else
> + i2c_bus->mode = BYTE_MODE;
> + }
> +
> + /* i2c timeout counter: use base clk4 1Mhz,
> + * per unit: 1/(1000/4096) = 4096us
> + */
> + ret = of_property_read_u32(dev->of_node,
> + "i2c-scl-clk-low-timeout-us",
> + &i2c_bus->timeout);
Strange layout.
> + if (ret < 0)
> + i2c_bus->timeout = 0;
Nit: This is not really needed since i2c_bus is kzalloc()'ed.
> + else
> + i2c_bus->timeout /= 4096;
> +
> + init_completion(&i2c_bus->cmd_complete);
> +
> + i2c_bus->irq = platform_get_irq(pdev, 0);
> + if (i2c_bus->irq < 0)
> + return i2c_bus->irq;
> +
> + platform_set_drvdata(pdev, i2c_bus);
> +
> + i2c_bus->clk = devm_clk_get(i2c_bus->dev, NULL);
> + if (IS_ERR(i2c_bus->clk))
> + return dev_err_probe(i2c_bus->dev, PTR_ERR(i2c_bus->clk),
"Can't get clock\n");
> +
> + i2c_bus->apb_clk = clk_get_rate(i2c_bus->clk);
> +
> + ret = of_property_read_u32(dev->of_node, "clock-frequency",
&i2c_bus->bus_frequency);
> + if (ret < 0) {
> + dev_warn(dev, "Could not read clock-frequency property\n");
> + i2c_bus->bus_frequency = 100000;
> + }
> +
> + /* Initialize the I2C adapter */
> + i2c_bus->adap.owner = THIS_MODULE;
> + i2c_bus->adap.algo = &i2c_ast2600_algorithm;
> + i2c_bus->adap.retries = 0;
> + i2c_bus->adap.dev.parent = i2c_bus->dev;
> + i2c_bus->adap.dev.of_node = dev->of_node;
> + i2c_bus->adap.algo_data = i2c_bus;
> + strscpy(i2c_bus->adap.name, pdev->name, sizeof(i2c_bus->adap.name));
> + i2c_set_adapdata(&i2c_bus->adap, i2c_bus);
> +
> + ast2600_i2c_init(i2c_bus);
> +
> + ret = devm_request_irq(dev, i2c_bus->irq, ast2600_i2c_bus_irq, 0,
> + dev_name(dev), i2c_bus);
> + if (ret < 0)
> + return dev_err_probe(dev, ret, "Unable to request irq %d\n",
i2c_bus->irq);
> +
> + if (of_property_read_bool(dev->of_node, "smbus-alert")) {
> + i2c_bus->alert_enable = 1;
> + i2c_bus->ara = i2c_new_smbus_alert_device(&i2c_bus->adap,
&i2c_bus->alert_data);
> + if (!i2c_bus->ara)
> + dev_warn(dev, "Failed to register ARA client\n");
> +
> + writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER |
AST2600_I2CM_SMBUS_ALT,
> + i2c_bus->reg_base + AST2600_I2CM_IER);
> + } else {
> + i2c_bus->alert_enable = 0;
> + /* Set interrupt generation of I2C master controller */
> + writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
> + i2c_bus->reg_base + AST2600_I2CM_IER);
> + }
> +
> + ret = i2c_add_adapter(&i2c_bus->adap);
Maybe devm_i2c_add_adapter() + remove function simplification.
This change + dmam_alloc_coherent() above + removing devm_free_irq()
should, all together, not chnage the order of the remove function IIUIC.
CJ
> + if (ret)
> + return ret;
> +
> + dev_info(dev, "%s [%d]: adapter [%d khz] mode [%d]\n",
> + dev->of_node->name, i2c_bus->adap.nr,
i2c_bus->bus_frequency / 1000,
> + i2c_bus->mode);
> +
> + return 0;
> +}
> +
> +static int ast2600_i2c_remove(struct platform_device *pdev)
> +{
> + struct ast2600_i2c_bus *i2c_bus = platform_get_drvdata(pdev);
> +
> + /* Disable everything. */
> + writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> + writel(0, i2c_bus->reg_base + AST2600_I2CM_IER);
> +
> + i2c_del_adapter(&i2c_bus->adap);
> + devm_free_irq(&pdev->dev, i2c_bus->irq, i2c_bus);
> +
> +#ifdef CONFIG_I2C_SLAVE
> + /* for memory buffer initial */
> + if (i2c_bus->mode == DMA_MODE)
> + dma_free_coherent(i2c_bus->dev, I2C_SLAVE_MSG_BUF_SIZE,
> + i2c_bus->slave_dma_buf, i2c_bus->slave_dma_addr);
> +#endif
> +
> + return 0;
> +}
> +
> +static struct platform_driver ast2600_i2c_bus_driver = {
> + .probe = ast2600_i2c_probe,
> + .remove = ast2600_i2c_remove,
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .of_match_table = ast2600_i2c_bus_of_table,
> + },
> +};
> +module_platform_driver(ast2600_i2c_bus_driver);
> +
> +MODULE_AUTHOR("Ryan Chen <ryan_chen at aspeedtech.com>");
> +MODULE_DESCRIPTION("ASPEED AST2600 I2C Controller Driver");
> +MODULE_LICENSE("GPL");
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