diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-npcm7xx.c | 608 |
1 files changed, 607 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c index 018abf8dda7e..a8e75c3484f1 100644 --- a/drivers/i2c/busses/i2c-npcm7xx.c +++ b/drivers/i2c/busses/i2c-npcm7xx.c @@ -71,6 +71,24 @@ enum i2c_state { I2C_STOP_PENDING, }; +#if IS_ENABLED(CONFIG_I2C_SLAVE) +/* Module supports setting multiple own slave addresses */ +enum i2c_addr { + I2C_SLAVE_ADDR1 = 0, + I2C_SLAVE_ADDR2, + I2C_SLAVE_ADDR3, + I2C_SLAVE_ADDR4, + I2C_SLAVE_ADDR5, + I2C_SLAVE_ADDR6, + I2C_SLAVE_ADDR7, + I2C_SLAVE_ADDR8, + I2C_SLAVE_ADDR9, + I2C_SLAVE_ADDR10, + I2C_GC_ADDR, + I2C_ARP_ADDR, +}; +#endif + /* init register and default value required to enable module */ #define NPCM_I2CSEGCTL 0xE4 #define NPCM_I2CSEGCTL_INIT_VAL 0x0333F000 @@ -98,6 +116,21 @@ enum i2c_state { #define NPCM_I2CADDR6 0x16 #define NPCM_I2CADDR10 0x17 +#if IS_ENABLED(CONFIG_I2C_SLAVE) +/* + * npcm_i2caddr array: + * The module supports having multiple own slave addresses. + * Since the addr regs are sprinkled all over the address space, + * use this array to get the address or each register. + */ +#define I2C_NUM_OWN_ADDR 10 +const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = { + NPCM_I2CADDR1, NPCM_I2CADDR2, NPCM_I2CADDR3, NPCM_I2CADDR4, + NPCM_I2CADDR5, NPCM_I2CADDR6, NPCM_I2CADDR7, NPCM_I2CADDR8, + NPCM_I2CADDR9, NPCM_I2CADDR10, +}; +#endif + #define NPCM_I2CCTL4 0x1A #define NPCM_I2CCTL5 0x1B #define NPCM_I2CSCLLT 0x1C /* SCL Low Time */ @@ -265,6 +298,16 @@ struct npcm_i2c { bool read_block_use; unsigned long int_time_stamp; unsigned long bus_freq; /* in Hz */ +#if IS_ENABLED(CONFIG_I2C_SLAVE) + u8 own_slave_addr; + struct i2c_client *slave; + int slv_rd_size; + int slv_rd_ind; + int slv_wr_size; + int slv_wr_ind; + u8 slv_rd_buf[I2C_HW_FIFO_SIZE]; + u8 slv_wr_buf[I2C_HW_FIFO_SIZE]; +#endif struct dentry *debugfs; /* debugfs device directory */ u64 ber_cnt; u64 rec_succ_cnt; @@ -296,6 +339,10 @@ static void npcm_i2c_init_params(struct npcm_i2c *bus) bus->int_time_stamp = 0; bus->PEC_use = false; bus->PEC_mask = 0; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) + bus->master_or_slave = I2C_SLAVE; +#endif } static inline void npcm_i2c_wr_byte(struct npcm_i2c *bus, u8 data) @@ -341,6 +388,18 @@ static void npcm_i2c_disable(struct npcm_i2c *bus) { u8 i2cctl2; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + int i; + + /* select bank 0 for I2C addresses */ + npcm_i2c_select_bank(bus, I2C_BANK_0); + + /* Slave addresses removal */ + for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR; i++) + iowrite8(0, bus->reg + npcm_i2caddr[i]); + + npcm_i2c_select_bank(bus, I2C_BANK_1); +#endif /* Disable module */ i2cctl2 = ioread8(bus->reg + NPCM_I2CCTL2); i2cctl2 = i2cctl2 & ~I2CCTL2_ENABLE; @@ -504,6 +563,61 @@ static inline void npcm_i2c_nack(struct npcm_i2c *bus) iowrite8(val, bus->reg + NPCM_I2CCTL1); } +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static void npcm_i2c_slave_int_enable(struct npcm_i2c *bus, bool enable) +{ + u8 i2cctl1; + + /* enable interrupt on slave match: */ + i2cctl1 = ioread8(bus->reg + NPCM_I2CCTL1); + i2cctl1 &= ~NPCM_I2CCTL1_RWS; + if (enable) + i2cctl1 |= NPCM_I2CCTL1_NMINTE; + else + i2cctl1 &= ~NPCM_I2CCTL1_NMINTE; + iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1); +} + +static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type, + u8 addr, bool enable) +{ + u8 i2cctl1; + u8 i2cctl3; + u8 sa_reg; + + sa_reg = (addr & 0x7F) | FIELD_PREP(NPCM_I2CADDR_SAEN, enable); + if (addr_type == I2C_GC_ADDR) { + i2cctl1 = ioread8(bus->reg + NPCM_I2CCTL1); + if (enable) + i2cctl1 |= NPCM_I2CCTL1_GCMEN; + else + i2cctl1 &= ~NPCM_I2CCTL1_GCMEN; + iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1); + return 0; + } + if (addr_type == I2C_ARP_ADDR) { + i2cctl3 = ioread8(bus->reg + NPCM_I2CCTL3); + if (enable) + i2cctl3 |= I2CCTL3_ARPMEN; + else + i2cctl3 &= ~I2CCTL3_ARPMEN; + iowrite8(i2cctl3, bus->reg + NPCM_I2CCTL3); + return 0; + } + if (addr_type >= I2C_ARP_ADDR) + return -EFAULT; + /* select bank 0 for address 3 to 10 */ + if (addr_type > I2C_SLAVE_ADDR2) + npcm_i2c_select_bank(bus, I2C_BANK_0); + /* Set and enable the address */ + iowrite8(sa_reg, bus->reg + npcm_i2caddr[addr_type]); + npcm_i2c_slave_int_enable(bus, enable); + if (addr_type > I2C_SLAVE_ADDR2) + npcm_i2c_select_bank(bus, I2C_BANK_1); + return 0; +} +#endif + static void npcm_i2c_reset(struct npcm_i2c *bus) { /* @@ -511,6 +625,9 @@ static void npcm_i2c_reset(struct npcm_i2c *bus) * is disabled. */ u8 i2cctl1; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + u8 addr; +#endif i2cctl1 = ioread8(bus->reg + NPCM_I2CCTL1); @@ -531,6 +648,13 @@ static void npcm_i2c_reset(struct npcm_i2c *bus) /* Clear all fifo bits: */ iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS); +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) { + addr = bus->slave->addr; + npcm_i2c_slave_enable(bus, I2C_SLAVE_ADDR1, addr, true); + } +#endif + bus->state = I2C_IDLE; } @@ -596,6 +720,10 @@ static void npcm_i2c_callback(struct npcm_i2c *bus, } bus->operation = I2C_NO_OPER; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) + bus->master_or_slave = I2C_SLAVE; +#endif } static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus) @@ -707,6 +835,459 @@ static void npcm_i2c_master_abort(struct npcm_i2c *bus) npcm_i2c_clear_master_status(bus); } +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static u8 npcm_i2c_get_slave_addr(struct npcm_i2c *bus, enum i2c_addr addr_type) +{ + u8 slave_add; + + /* select bank 0 for address 3 to 10 */ + if (addr_type > I2C_SLAVE_ADDR2) + npcm_i2c_select_bank(bus, I2C_BANK_0); + + slave_add = ioread8(bus->reg + npcm_i2caddr[(int)addr_type]); + + if (addr_type > I2C_SLAVE_ADDR2) + npcm_i2c_select_bank(bus, I2C_BANK_1); + + return slave_add; +} + +static int npcm_i2c_remove_slave_addr(struct npcm_i2c *bus, u8 slave_add) +{ + int i; + + /* Set the enable bit */ + slave_add |= 0x80; + npcm_i2c_select_bank(bus, I2C_BANK_0); + for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR; i++) { + if (ioread8(bus->reg + npcm_i2caddr[i]) == slave_add) + iowrite8(0, bus->reg + npcm_i2caddr[i]); + } + npcm_i2c_select_bank(bus, I2C_BANK_1); + return 0; +} + +static void npcm_i2c_write_fifo_slave(struct npcm_i2c *bus, u16 max_bytes) +{ + /* + * Fill the FIFO, while the FIFO is not full and there are more bytes + * to write + */ + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_tx_fifo(bus); + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + while (max_bytes-- && I2C_HW_FIFO_SIZE != npcm_i2c_fifo_usage(bus)) { + if (bus->slv_wr_size <= 0) + break; + bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE; + npcm_i2c_wr_byte(bus, bus->slv_wr_buf[bus->slv_wr_ind]); + bus->slv_wr_ind++; + bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE; + bus->slv_wr_size--; + } +} + +static void npcm_i2c_read_fifo_slave(struct npcm_i2c *bus, u8 bytes_in_fifo) +{ + u8 data; + + if (!bus->slave) + return; + + while (bytes_in_fifo--) { + data = npcm_i2c_rd_byte(bus); + + bus->slv_rd_ind = bus->slv_rd_ind % I2C_HW_FIFO_SIZE; + bus->slv_rd_buf[bus->slv_rd_ind] = data; + bus->slv_rd_ind++; + + /* 1st byte is length in block protocol: */ + if (bus->slv_rd_ind == 1 && bus->read_block_use) + bus->slv_rd_size = data + bus->PEC_use + 1; + } +} + +static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus) +{ + int i; + u8 value; + int ind; + int ret = bus->slv_wr_ind; + + /* fill a cyclic buffer */ + for (i = 0; i < I2C_HW_FIFO_SIZE; i++) { + if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE) + break; + i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value); + ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE; + bus->slv_wr_buf[ind] = value; + bus->slv_wr_size++; + i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value); + } + return I2C_HW_FIFO_SIZE - ret; +} + +static void npcm_i2c_slave_send_rd_buf(struct npcm_i2c *bus) +{ + int i; + + for (i = 0; i < bus->slv_rd_ind; i++) + i2c_slave_event(bus->slave, I2C_SLAVE_WRITE_RECEIVED, + &bus->slv_rd_buf[i]); + /* + * once we send bytes up, need to reset the counter of the wr buf + * got data from master (new offset in device), ignore wr fifo: + */ + if (bus->slv_rd_ind) { + bus->slv_wr_size = 0; + bus->slv_wr_ind = 0; + } + + bus->slv_rd_ind = 0; + bus->slv_rd_size = bus->adap.quirks->max_read_len; + + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); +} + +static void npcm_i2c_slave_receive(struct npcm_i2c *bus, u16 nread, + u8 *read_data) +{ + bus->state = I2C_OPER_STARTED; + bus->operation = I2C_READ_OPER; + bus->slv_rd_size = nread; + bus->slv_rd_ind = 0; + + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL); + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_clear_rx_fifo(bus); +} + +static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite, + u8 *write_data) +{ + if (nwrite == 0) + return; + + bus->state = I2C_OPER_STARTED; + bus->operation = I2C_WRITE_OPER; + + /* get the next buffer */ + npcm_i2c_slave_get_wr_buf(bus); + npcm_i2c_write_fifo_slave(bus, nwrite); +} + +/* + * npcm_i2c_slave_wr_buf_sync: + * currently slave IF only supports single byte operations. + * in order to utilyze the npcm HW FIFO, the driver will ask for 16 bytes + * at a time, pack them in buffer, and then transmit them all together + * to the FIFO and onward to the bus. + * NACK on read will be once reached to bus->adap->quirks->max_read_len. + * sending a NACK wherever the backend requests for it is not supported. + * the next two functions allow reading to local buffer before writing it all + * to the HW FIFO. + */ +static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus) +{ + int left_in_fifo; + + left_in_fifo = FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES, + ioread8(bus->reg + NPCM_I2CTXF_STS)); + + /* fifo already full: */ + if (left_in_fifo >= I2C_HW_FIFO_SIZE || + bus->slv_wr_size >= I2C_HW_FIFO_SIZE) + return; + + /* update the wr fifo index back to the untransmitted bytes: */ + bus->slv_wr_ind = bus->slv_wr_ind - left_in_fifo; + bus->slv_wr_size = bus->slv_wr_size + left_in_fifo; + + if (bus->slv_wr_ind < 0) + bus->slv_wr_ind += I2C_HW_FIFO_SIZE; +} + +static void npcm_i2c_slave_rd_wr(struct npcm_i2c *bus) +{ + if (NPCM_I2CST_XMIT & ioread8(bus->reg + NPCM_I2CST)) { + /* + * Slave got an address match with direction bit 1 so it should + * transmit data. Write till the master will NACK + */ + bus->operation = I2C_WRITE_OPER; + npcm_i2c_slave_xmit(bus, bus->adap.quirks->max_write_len, + bus->slv_wr_buf); + } else { + /* + * Slave got an address match with direction bit 0 so it should + * receive data. + * this module does not support saying no to bytes. + * it will always ACK. + */ + bus->operation = I2C_READ_OPER; + npcm_i2c_read_fifo_slave(bus, npcm_i2c_fifo_usage(bus)); + bus->stop_ind = I2C_SLAVE_RCV_IND; + npcm_i2c_slave_send_rd_buf(bus); + npcm_i2c_slave_receive(bus, bus->adap.quirks->max_read_len, + bus->slv_rd_buf); + } +} + +static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus) +{ + u8 val; + irqreturn_t ret = IRQ_NONE; + u8 i2cst = ioread8(bus->reg + NPCM_I2CST); + + /* Slave: A NACK has occurred */ + if (NPCM_I2CST_NEGACK & i2cst) { + bus->stop_ind = I2C_NACK_IND; + npcm_i2c_slave_wr_buf_sync(bus); + if (bus->fifo_use) + /* clear the FIFO */ + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, + bus->reg + NPCM_I2CFIF_CTS); + + /* In slave write, NACK is OK, otherwise it is a problem */ + bus->stop_ind = I2C_NO_STATUS_IND; + bus->operation = I2C_NO_OPER; + bus->own_slave_addr = 0xFF; + + /* + * Slave has to wait for STOP to decide this is the end + * of the transaction. tx is not yet considered as done + */ + iowrite8(NPCM_I2CST_NEGACK, bus->reg + NPCM_I2CST); + + ret = IRQ_HANDLED; + } + + /* Slave mode: a Bus Error (BER) has been identified */ + if (NPCM_I2CST_BER & i2cst) { + /* + * Check whether bus arbitration or Start or Stop during data + * xfer bus arbitration problem should not result in recovery + */ + bus->stop_ind = I2C_BUS_ERR_IND; + + /* wait for bus busy before clear fifo */ + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS); + + bus->state = I2C_IDLE; + + /* + * in BER case we might get 2 interrupts: one for slave one for + * master ( for a channel which is master\slave switching) + */ + if (completion_done(&bus->cmd_complete) == false) { + bus->cmd_err = -EIO; + complete(&bus->cmd_complete); + } + bus->own_slave_addr = 0xFF; + iowrite8(NPCM_I2CST_BER, bus->reg + NPCM_I2CST); + ret = IRQ_HANDLED; + } + + /* A Slave Stop Condition has been identified */ + if (NPCM_I2CST_SLVSTP & i2cst) { + u8 bytes_in_fifo = npcm_i2c_fifo_usage(bus); + + bus->stop_ind = I2C_SLAVE_DONE_IND; + + if (bus->operation == I2C_READ_OPER) + npcm_i2c_read_fifo_slave(bus, bytes_in_fifo); + + /* if the buffer is empty nothing will be sent */ + npcm_i2c_slave_send_rd_buf(bus); + + /* Slave done transmitting or receiving */ + bus->stop_ind = I2C_NO_STATUS_IND; + + /* + * Note, just because we got here, it doesn't mean we through + * away the wr buffer. + * we keep it until the next received offset. + */ + bus->operation = I2C_NO_OPER; + bus->own_slave_addr = 0xFF; + i2c_slave_event(bus->slave, I2C_SLAVE_STOP, 0); + iowrite8(NPCM_I2CST_SLVSTP, bus->reg + NPCM_I2CST); + if (bus->fifo_use) { + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); + npcm_i2c_clear_tx_fifo(bus); + + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, + bus->reg + NPCM_I2CFIF_CTS); + } + bus->state = I2C_IDLE; + ret = IRQ_HANDLED; + } + + /* restart condition occurred and Rx-FIFO was not empty */ + if (bus->fifo_use && FIELD_GET(NPCM_I2CFIF_CTS_SLVRSTR, + ioread8(bus->reg + NPCM_I2CFIF_CTS))) { + bus->stop_ind = I2C_SLAVE_RESTART_IND; + bus->master_or_slave = I2C_SLAVE; + if (bus->operation == I2C_READ_OPER) + npcm_i2c_read_fifo_slave(bus, npcm_i2c_fifo_usage(bus)); + bus->operation = I2C_WRITE_OPER; + iowrite8(0, bus->reg + NPCM_I2CRXF_CTL); + val = NPCM_I2CFIF_CTS_CLR_FIFO | NPCM_I2CFIF_CTS_SLVRSTR | + NPCM_I2CFIF_CTS_RXF_TXE; + iowrite8(val, bus->reg + NPCM_I2CFIF_CTS); + npcm_i2c_slave_rd_wr(bus); + ret = IRQ_HANDLED; + } + + /* A Slave Address Match has been identified */ + if (NPCM_I2CST_NMATCH & i2cst) { + u8 info = 0; + + /* Address match automatically implies slave mode */ + bus->master_or_slave = I2C_SLAVE; + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); + npcm_i2c_clear_tx_fifo(bus); + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL); + if (NPCM_I2CST_XMIT & i2cst) { + bus->operation = I2C_WRITE_OPER; + } else { + i2c_slave_event(bus->slave, I2C_SLAVE_WRITE_REQUESTED, + &info); + bus->operation = I2C_READ_OPER; + } + if (bus->own_slave_addr == 0xFF) { + /* Check which type of address match */ + val = ioread8(bus->reg + NPCM_I2CCST); + if (NPCM_I2CCST_MATCH & val) { + u16 addr; + enum i2c_addr eaddr; + u8 i2ccst2; + u8 i2ccst3; + + i2ccst3 = ioread8(bus->reg + NPCM_I2CCST3); + i2ccst2 = ioread8(bus->reg + NPCM_I2CCST2); + + /* + * the i2c module can response to 10 own SA. + * check which one was addressed by the master. + * repond to the first one. + */ + addr = ((i2ccst3 & 0x07) << 7) | + (i2ccst2 & 0x7F); + info = ffs(addr); + eaddr = (enum i2c_addr)info; + addr = npcm_i2c_get_slave_addr(bus, eaddr); + addr &= 0x7F; + bus->own_slave_addr = addr; + if (bus->PEC_mask & BIT(info)) + bus->PEC_use = true; + else + bus->PEC_use = false; + } else { + if (NPCM_I2CCST_GCMATCH & val) + bus->own_slave_addr = 0; + if (NPCM_I2CCST_ARPMATCH & val) + bus->own_slave_addr = 0x61; + } + } else { + /* + * Slave match can happen in two options: + * 1. Start, SA, read (slave read without further ado) + * 2. Start, SA, read, data, restart, SA, read, ... + * (slave read in fragmented mode) + * 3. Start, SA, write, data, restart, SA, read, .. + * (regular write-read mode) + */ + if ((bus->state == I2C_OPER_STARTED && + bus->operation == I2C_READ_OPER && + bus->stop_ind == I2C_SLAVE_XMIT_IND) || + bus->stop_ind == I2C_SLAVE_RCV_IND) { + /* slave tx after slave rx w/o STOP */ + bus->stop_ind = I2C_SLAVE_RESTART_IND; + } + } + + if (NPCM_I2CST_XMIT & i2cst) + bus->stop_ind = I2C_SLAVE_XMIT_IND; + else + bus->stop_ind = I2C_SLAVE_RCV_IND; + bus->state = I2C_SLAVE_MATCH; + npcm_i2c_slave_rd_wr(bus); + iowrite8(NPCM_I2CST_NMATCH, bus->reg + NPCM_I2CST); + ret = IRQ_HANDLED; + } + + /* Slave SDA status is set - tx or rx */ + if ((NPCM_I2CST_SDAST & i2cst) || + (bus->fifo_use && + (npcm_i2c_tx_fifo_empty(bus) || npcm_i2c_rx_fifo_full(bus)))) { + npcm_i2c_slave_rd_wr(bus); + iowrite8(NPCM_I2CST_SDAST, bus->reg + NPCM_I2CST); + ret = IRQ_HANDLED; + } /* SDAST */ + + return ret; +} + +static int npcm_i2c_reg_slave(struct i2c_client *client) +{ + unsigned long lock_flags; + struct npcm_i2c *bus = i2c_get_adapdata(client->adapter); + + bus->slave = client; + + if (!bus->slave) + return -EINVAL; + + if (client->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + spin_lock_irqsave(&bus->lock, lock_flags); + + npcm_i2c_init_params(bus); + bus->slv_rd_size = 0; + bus->slv_wr_size = 0; + bus->slv_rd_ind = 0; + bus->slv_wr_ind = 0; + if (client->flags & I2C_CLIENT_PEC) + bus->PEC_use = true; + + dev_info(bus->dev, "i2c%d register slave SA=0x%x, PEC=%d\n", bus->num, + client->addr, bus->PEC_use); + + npcm_i2c_slave_enable(bus, I2C_SLAVE_ADDR1, client->addr, true); + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_slave_int_enable(bus, true); + + spin_unlock_irqrestore(&bus->lock, lock_flags); + return 0; +} + +static int npcm_i2c_unreg_slave(struct i2c_client *client) +{ + struct npcm_i2c *bus = client->adapter->algo_data; + unsigned long lock_flags; + + spin_lock_irqsave(&bus->lock, lock_flags); + if (!bus->slave) { + spin_unlock_irqrestore(&bus->lock, lock_flags); + return -EINVAL; + } + npcm_i2c_slave_int_enable(bus, false); + npcm_i2c_remove_slave_addr(bus, client->addr); + bus->slave = NULL; + spin_unlock_irqrestore(&bus->lock, lock_flags); + return 0; +} +#endif /* CONFIG_I2C_SLAVE */ + static void npcm_i2c_master_fifo_read(struct npcm_i2c *bus) { int rcount; @@ -1372,6 +1953,9 @@ static int __npcm_i2c_init(struct npcm_i2c *bus, struct platform_device *pdev) bus->state = I2C_DISABLE; bus->master_or_slave = I2C_SLAVE; bus->int_time_stamp = 0; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + bus->slave = NULL; +#endif ret = device_property_read_u32(&pdev->dev, "clock-frequency", &clk_freq_hz); @@ -1401,6 +1985,12 @@ static irqreturn_t npcm_i2c_bus_irq(int irq, void *dev_id) if (!npcm_i2c_int_master_handler(bus)) return IRQ_HANDLED; } +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) { + bus->master_or_slave = I2C_SLAVE; + return npcm_i2c_int_slave_handler(bus); + } +#endif return IRQ_NONE; } @@ -1520,6 +2110,11 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, */ spin_lock_irqsave(&bus->lock, flags); bus_busy = ioread8(bus->reg + NPCM_I2CCST) & NPCM_I2CCST_BB; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (!bus_busy && bus->slave) + iowrite8((bus->slave->addr & 0x7F), + bus->reg + NPCM_I2CADDR1); +#endif spin_unlock_irqrestore(&bus->lock, flags); } while (time_is_after_jiffies(time_left) && bus_busy); @@ -1564,6 +2159,12 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, if (bus->cmd_err == -EAGAIN) ret = i2c_recover_bus(adap); +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* reenable slave if it was enabled */ + if (bus->slave) + iowrite8((bus->slave->addr & 0x7F) | NPCM_I2CADDR_SAEN, + bus->reg + NPCM_I2CADDR1); +#endif return bus->cmd_err; } @@ -1572,7 +2173,8 @@ static u32 npcm_i2c_functionality(struct i2c_adapter *adap) return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA | - I2C_FUNC_SMBUS_PEC; + I2C_FUNC_SMBUS_PEC | + I2C_FUNC_SLAVE; } static const struct i2c_adapter_quirks npcm_i2c_quirks = { @@ -1584,6 +2186,10 @@ static const struct i2c_adapter_quirks npcm_i2c_quirks = { static const struct i2c_algorithm npcm_i2c_algo = { .master_xfer = npcm_i2c_master_xfer, .functionality = npcm_i2c_functionality, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_slave = npcm_i2c_reg_slave, + .unreg_slave = npcm_i2c_unreg_slave, +#endif }; /* i2c debugfs directory: used to keep health monitor of i2c devices */ |