From a5969cabbb4660eab42b6ef0412cbbd1200cf14d Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Sat, 12 Oct 2024 07:10:09 +0000 Subject: [PATCH] 修改led为gpio --- kernel/drivers/i2c/busses/i2c-aspeed.c | 279 +++++++++++++++++++++++++++++++++++++++---------------- 1 files changed, 196 insertions(+), 83 deletions(-) diff --git a/kernel/drivers/i2c/busses/i2c-aspeed.c b/kernel/drivers/i2c/busses/i2c-aspeed.c index d9401b5..dac46bc 100644 --- a/kernel/drivers/i2c/busses/i2c-aspeed.c +++ b/kernel/drivers/i2c/busses/i2c-aspeed.c @@ -1,13 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Aspeed 24XX/25XX I2C Controller. * * Copyright (C) 2012-2017 ASPEED Technology Inc. * Copyright 2017 IBM Corporation * Copyright 2017 Google, Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. */ #include <linux/clk.h> @@ -72,6 +69,7 @@ * These share bit definitions, so use the same values for the enable & * status bits. */ +#define ASPEED_I2CD_INTR_RECV_MASK 0xf000ffff #define ASPEED_I2CD_INTR_SDA_DL_TIMEOUT BIT(14) #define ASPEED_I2CD_INTR_BUS_RECOVER_DONE BIT(13) #define ASPEED_I2CD_INTR_SLAVE_MATCH BIT(7) @@ -82,6 +80,11 @@ #define ASPEED_I2CD_INTR_RX_DONE BIT(2) #define ASPEED_I2CD_INTR_TX_NAK BIT(1) #define ASPEED_I2CD_INTR_TX_ACK BIT(0) +#define ASPEED_I2CD_INTR_MASTER_ERRORS \ + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ + ASPEED_I2CD_INTR_ABNORMAL | \ + ASPEED_I2CD_INTR_ARBIT_LOSS) #define ASPEED_I2CD_INTR_ALL \ (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \ @@ -106,12 +109,19 @@ #define ASPEED_I2CD_S_TX_CMD BIT(2) #define ASPEED_I2CD_M_TX_CMD BIT(1) #define ASPEED_I2CD_M_START_CMD BIT(0) +#define ASPEED_I2CD_MASTER_CMDS_MASK \ + (ASPEED_I2CD_M_STOP_CMD | \ + ASPEED_I2CD_M_S_RX_CMD_LAST | \ + ASPEED_I2CD_M_RX_CMD | \ + ASPEED_I2CD_M_TX_CMD | \ + ASPEED_I2CD_M_START_CMD) /* 0x18 : I2CD Slave Device Address Register */ #define ASPEED_I2CD_DEV_ADDR_MASK GENMASK(6, 0) enum aspeed_i2c_master_state { ASPEED_I2C_MASTER_INACTIVE, + ASPEED_I2C_MASTER_PENDING, ASPEED_I2C_MASTER_START, ASPEED_I2C_MASTER_TX_FIRST, ASPEED_I2C_MASTER_TX, @@ -121,12 +131,13 @@ }; enum aspeed_i2c_slave_state { - ASPEED_I2C_SLAVE_STOP, + ASPEED_I2C_SLAVE_INACTIVE, ASPEED_I2C_SLAVE_START, ASPEED_I2C_SLAVE_READ_REQUESTED, ASPEED_I2C_SLAVE_READ_PROCESSED, ASPEED_I2C_SLAVE_WRITE_REQUESTED, ASPEED_I2C_SLAVE_WRITE_RECEIVED, + ASPEED_I2C_SLAVE_STOP, }; struct aspeed_i2c_bus { @@ -151,6 +162,8 @@ int cmd_err; /* Protected only by i2c_lock_bus */ int master_xfer_result; + /* Multi-master */ + bool multi_master; #if IS_ENABLED(CONFIG_I2C_SLAVE) struct i2c_client *slave; enum aspeed_i2c_slave_state slave_state; @@ -228,32 +241,26 @@ } #if IS_ENABLED(CONFIG_I2C_SLAVE) -static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) +static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status) { - u32 command, irq_status, status_ack = 0; + u32 command, irq_handled = 0; struct i2c_client *slave = bus->slave; - bool irq_handled = true; u8 value; - if (!slave) { - irq_handled = false; - goto out; - } + if (!slave) + return 0; command = readl(bus->base + ASPEED_I2C_CMD_REG); - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); /* Slave was requested, restart state machine. */ if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { - status_ack |= ASPEED_I2CD_INTR_SLAVE_MATCH; + irq_handled |= ASPEED_I2CD_INTR_SLAVE_MATCH; bus->slave_state = ASPEED_I2C_SLAVE_START; } /* Slave is not currently active, irq was for someone else. */ - if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) { - irq_handled = false; - goto out; - } + if (bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE) + return irq_handled; dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n", irq_status, command); @@ -270,34 +277,36 @@ bus->slave_state = ASPEED_I2C_SLAVE_WRITE_REQUESTED; } - status_ack |= ASPEED_I2CD_INTR_RX_DONE; + irq_handled |= ASPEED_I2CD_INTR_RX_DONE; } /* Slave was asked to stop. */ if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { - status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP; + irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP; bus->slave_state = ASPEED_I2C_SLAVE_STOP; } - if (irq_status & ASPEED_I2CD_INTR_TX_NAK) { - status_ack |= ASPEED_I2CD_INTR_TX_NAK; + if (irq_status & ASPEED_I2CD_INTR_TX_NAK && + bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) { + irq_handled |= ASPEED_I2CD_INTR_TX_NAK; bus->slave_state = ASPEED_I2C_SLAVE_STOP; } switch (bus->slave_state) { case ASPEED_I2C_SLAVE_READ_REQUESTED: - if (irq_status & ASPEED_I2CD_INTR_TX_ACK) + if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_ACK)) dev_err(bus->dev, "Unexpected ACK on read request.\n"); bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED; - i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); break; case ASPEED_I2C_SLAVE_READ_PROCESSED: - status_ack |= ASPEED_I2CD_INTR_TX_ACK; - if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK)) + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { dev_err(bus->dev, "Expected ACK after processed read.\n"); + break; + } + irq_handled |= ASPEED_I2CD_INTR_TX_ACK; i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); @@ -311,20 +320,18 @@ break; case ASPEED_I2C_SLAVE_STOP: i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE; + break; + case ASPEED_I2C_SLAVE_START: + /* Slave was just started. Waiting for the next event. */; break; default: - dev_err(bus->dev, "unhandled slave_state: %d\n", + dev_err(bus->dev, "unknown slave_state: %d\n", bus->slave_state); + bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE; break; } - if (status_ack != irq_status) - dev_err(bus->dev, - "irq handled != irq. expected %x, but was %x\n", - irq_status, status_ack); - writel(status_ack, bus->base + ASPEED_I2C_INTR_STS_REG); - -out: return irq_handled; } #endif /* CONFIG_I2C_SLAVE */ @@ -335,6 +342,18 @@ u32 command = ASPEED_I2CD_M_START_CMD | ASPEED_I2CD_M_TX_CMD; struct i2c_msg *msg = &bus->msgs[bus->msgs_index]; u8 slave_addr = i2c_8bit_addr_from_msg(msg); + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* + * If it's requested in the middle of a slave session, set the master + * state to 'pending' then H/W will continue handling this master + * command when the bus comes back to the idle state. + */ + if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE) { + bus->master_state = ASPEED_I2C_MASTER_PENDING; + return; + } +#endif /* CONFIG_I2C_SLAVE */ bus->master_state = ASPEED_I2C_MASTER_START; bus->buf_index = 0; @@ -381,20 +400,16 @@ return 0; } -static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) +static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status) { - u32 irq_status, status_ack = 0, command = 0; + u32 irq_handled = 0, command = 0; struct i2c_msg *msg; u8 recv_byte; int ret; - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); - /* Ack all interrupt bits. */ - writel(irq_status, bus->base + ASPEED_I2C_INTR_STS_REG); - if (irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { bus->master_state = ASPEED_I2C_MASTER_INACTIVE; - status_ack |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE; + irq_handled |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE; goto out_complete; } @@ -404,19 +419,29 @@ * INACTIVE state. */ ret = aspeed_i2c_is_irq_error(irq_status); - if (ret < 0) { + if (ret) { dev_dbg(bus->dev, "received error interrupt: 0x%08x\n", irq_status); - bus->cmd_err = ret; - bus->master_state = ASPEED_I2C_MASTER_INACTIVE; - goto out_complete; + irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_ERRORS); + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) { + bus->cmd_err = ret; + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + goto out_complete; + } } + + /* Master is not currently active, irq was for someone else. */ + if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE || + bus->master_state == ASPEED_I2C_MASTER_PENDING) + goto out_no_complete; /* We are in an invalid state; reset bus to a known state. */ if (!bus->msgs) { - dev_err(bus->dev, "bus in unknown state\n"); + dev_err(bus->dev, "bus in unknown state. irq_status: 0x%x\n", + irq_status); bus->cmd_err = -EIO; - if (bus->master_state != ASPEED_I2C_MASTER_STOP) + if (bus->master_state != ASPEED_I2C_MASTER_STOP && + bus->master_state != ASPEED_I2C_MASTER_INACTIVE) aspeed_i2c_do_stop(bus); goto out_no_complete; } @@ -428,14 +453,37 @@ * then update the state and handle the new state below. */ if (bus->master_state == ASPEED_I2C_MASTER_START) { +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* + * If a peer master starts a xfer immediately after it queues a + * master command, clear the queued master command and change + * its state to 'pending'. To simplify handling of pending + * cases, it uses S/W solution instead of H/W command queue + * handling. + */ + if (unlikely(irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH)) { + writel(readl(bus->base + ASPEED_I2C_CMD_REG) & + ~ASPEED_I2CD_MASTER_CMDS_MASK, + bus->base + ASPEED_I2C_CMD_REG); + bus->master_state = ASPEED_I2C_MASTER_PENDING; + dev_dbg(bus->dev, + "master goes pending due to a slave start\n"); + goto out_no_complete; + } +#endif /* CONFIG_I2C_SLAVE */ if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_NAK))) { + bus->cmd_err = -ENXIO; + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + goto out_complete; + } pr_devel("no slave present at %02x\n", msg->addr); - status_ack |= ASPEED_I2CD_INTR_TX_NAK; + irq_handled |= ASPEED_I2CD_INTR_TX_NAK; bus->cmd_err = -ENXIO; aspeed_i2c_do_stop(bus); goto out_no_complete; } - status_ack |= ASPEED_I2CD_INTR_TX_ACK; + irq_handled |= ASPEED_I2CD_INTR_TX_ACK; if (msg->len == 0) { /* SMBUS_QUICK */ aspeed_i2c_do_stop(bus); goto out_no_complete; @@ -450,14 +498,14 @@ case ASPEED_I2C_MASTER_TX: if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) { dev_dbg(bus->dev, "slave NACKed TX\n"); - status_ack |= ASPEED_I2CD_INTR_TX_NAK; + irq_handled |= ASPEED_I2CD_INTR_TX_NAK; goto error_and_stop; } else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { dev_err(bus->dev, "slave failed to ACK TX\n"); goto error_and_stop; } - status_ack |= ASPEED_I2CD_INTR_TX_ACK; - /* fallthrough intended */ + irq_handled |= ASPEED_I2CD_INTR_TX_ACK; + fallthrough; case ASPEED_I2C_MASTER_TX_FIRST: if (bus->buf_index < msg->len) { bus->master_state = ASPEED_I2C_MASTER_TX; @@ -473,13 +521,13 @@ /* RX may not have completed yet (only address cycle) */ if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE)) goto out_no_complete; - /* fallthrough intended */ + fallthrough; case ASPEED_I2C_MASTER_RX: if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) { dev_err(bus->dev, "master failed to RX\n"); goto error_and_stop; } - status_ack |= ASPEED_I2CD_INTR_RX_DONE; + irq_handled |= ASPEED_I2CD_INTR_RX_DONE; recv_byte = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; msg->buf[bus->buf_index++] = recv_byte; @@ -507,11 +555,13 @@ goto out_no_complete; case ASPEED_I2C_MASTER_STOP: if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) { - dev_err(bus->dev, "master failed to STOP\n"); + dev_err(bus->dev, + "master failed to STOP. irq_status:0x%x\n", + irq_status); bus->cmd_err = -EIO; /* Do not STOP as we have already tried. */ } else { - status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP; + irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP; } bus->master_state = ASPEED_I2C_MASTER_INACTIVE; @@ -541,35 +591,70 @@ bus->master_xfer_result = bus->msgs_index + 1; complete(&bus->cmd_complete); out_no_complete: - if (irq_status != status_ack) - dev_err(bus->dev, - "irq handled != irq. expected 0x%08x, but was 0x%08x\n", - irq_status, status_ack); - return !!irq_status; + return irq_handled; } static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) { struct aspeed_i2c_bus *bus = dev_id; - bool ret; + u32 irq_received, irq_remaining, irq_handled; spin_lock(&bus->lock); + irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG); + /* Ack all interrupts except for Rx done */ + writel(irq_received & ~ASPEED_I2CD_INTR_RX_DONE, + bus->base + ASPEED_I2C_INTR_STS_REG); + readl(bus->base + ASPEED_I2C_INTR_STS_REG); + irq_received &= ASPEED_I2CD_INTR_RECV_MASK; + irq_remaining = irq_received; #if IS_ENABLED(CONFIG_I2C_SLAVE) - if (IS_ENABLED(CONFIG_I2C_SLAVE) && aspeed_i2c_slave_irq(bus)) { - dev_dbg(bus->dev, "irq handled by slave.\n"); - ret = true; - goto out; + /* + * In most cases, interrupt bits will be set one by one, although + * multiple interrupt bits could be set at the same time. It's also + * possible that master interrupt bits could be set along with slave + * interrupt bits. Each case needs to be handled using corresponding + * handlers depending on the current state. + */ + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE && + bus->master_state != ASPEED_I2C_MASTER_PENDING) { + irq_handled = aspeed_i2c_master_irq(bus, irq_remaining); + irq_remaining &= ~irq_handled; + if (irq_remaining) + irq_handled |= aspeed_i2c_slave_irq(bus, irq_remaining); + } else { + irq_handled = aspeed_i2c_slave_irq(bus, irq_remaining); + irq_remaining &= ~irq_handled; + if (irq_remaining) + irq_handled |= aspeed_i2c_master_irq(bus, + irq_remaining); } + + /* + * Start a pending master command at here if a slave operation is + * completed. + */ + if (bus->master_state == ASPEED_I2C_MASTER_PENDING && + bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE) + aspeed_i2c_do_start(bus); +#else + irq_handled = aspeed_i2c_master_irq(bus, irq_remaining); #endif /* CONFIG_I2C_SLAVE */ - ret = aspeed_i2c_master_irq(bus); + irq_remaining &= ~irq_handled; + if (irq_remaining) + dev_err(bus->dev, + "irq handled != irq. expected 0x%08x, but was 0x%08x\n", + irq_received, irq_handled); -#if IS_ENABLED(CONFIG_I2C_SLAVE) -out: -#endif + /* Ack Rx done */ + if (irq_received & ASPEED_I2CD_INTR_RX_DONE) { + writel(ASPEED_I2CD_INTR_RX_DONE, + bus->base + ASPEED_I2C_INTR_STS_REG); + readl(bus->base + ASPEED_I2C_INTR_STS_REG); + } spin_unlock(&bus->lock); - return ret ? IRQ_HANDLED : IRQ_NONE; + return irq_remaining ? IRQ_NONE : IRQ_HANDLED; } static int aspeed_i2c_master_xfer(struct i2c_adapter *adap, @@ -577,15 +662,16 @@ { struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap); unsigned long time_left, flags; - int ret = 0; spin_lock_irqsave(&bus->lock, flags); bus->cmd_err = 0; - /* If bus is busy, attempt recovery. We assume a single master - * environment. - */ - if (readl(bus->base + ASPEED_I2C_CMD_REG) & ASPEED_I2CD_BUS_BUSY_STS) { + /* If bus is busy in a single master environment, attempt recovery. */ + if (!bus->multi_master && + (readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_BUS_BUSY_STS)) { + int ret; + spin_unlock_irqrestore(&bus->lock, flags); ret = aspeed_i2c_recover_bus(bus); if (ret) @@ -605,10 +691,32 @@ time_left = wait_for_completion_timeout(&bus->cmd_complete, bus->adap.timeout); - if (time_left == 0) + if (time_left == 0) { + /* + * In a multi-master setup, if a timeout occurs, attempt + * recovery. But if the bus is idle, we still need to reset the + * i2c controller to clear the remaining interrupts. + */ + if (bus->multi_master && + (readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_BUS_BUSY_STS)) + aspeed_i2c_recover_bus(bus); + else + aspeed_i2c_reset(bus); + + /* + * If timed out and the state is still pending, drop the pending + * master command. + */ + spin_lock_irqsave(&bus->lock, flags); + if (bus->master_state == ASPEED_I2C_MASTER_PENDING) + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + spin_unlock_irqrestore(&bus->lock, flags); + return -ETIMEDOUT; - else - return bus->master_xfer_result; + } + + return bus->master_xfer_result; } static u32 aspeed_i2c_functionality(struct i2c_adapter *adap) @@ -648,7 +756,7 @@ __aspeed_i2c_reg_slave(bus, client->addr); bus->slave = client; - bus->slave_state = ASPEED_I2C_SLAVE_STOP; + bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE; spin_unlock_irqrestore(&bus->lock, flags); return 0; @@ -803,7 +911,9 @@ if (ret < 0) return ret; - if (!of_property_read_bool(pdev->dev.of_node, "multi-master")) + if (of_property_read_bool(pdev->dev.of_node, "multi-master")) + bus->multi_master = true; + else fun_ctrl_reg |= ASPEED_I2CD_MULTI_MASTER_DIS; /* Enable Master Mode */ @@ -850,6 +960,10 @@ .compatible = "aspeed,ast2500-i2c-bus", .data = aspeed_i2c_25xx_get_clk_reg_val, }, + { + .compatible = "aspeed,ast2600-i2c-bus", + .data = aspeed_i2c_25xx_get_clk_reg_val, + }, { }, }; MODULE_DEVICE_TABLE(of, aspeed_i2c_bus_of_table); @@ -891,7 +1005,7 @@ if (ret < 0) { dev_err(&pdev->dev, "Could not read bus-frequency property\n"); - bus->bus_frequency = 100000; + bus->bus_frequency = I2C_MAX_STANDARD_MODE_FREQ; } match = of_match_node(aspeed_i2c_bus_of_table, pdev->dev.of_node); @@ -906,7 +1020,6 @@ init_completion(&bus->cmd_complete); bus->adap.owner = THIS_MODULE; bus->adap.retries = 0; - bus->adap.timeout = 5 * HZ; bus->adap.algo = &aspeed_i2c_algo; bus->adap.dev.parent = &pdev->dev; bus->adap.dev.of_node = pdev->dev.of_node; -- Gitblit v1.6.2