Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index a19fbff..7b098ff 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/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>
@@ -82,6 +79,11 @@
#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 +108,19 @@
#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 +130,13 @@
};
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 {
@@ -137,7 +147,8 @@
/* Synchronizes I/O mem access to base. */
spinlock_t lock;
struct completion cmd_complete;
- u32 (*get_clk_reg_val)(u32 divisor);
+ u32 (*get_clk_reg_val)(struct device *dev,
+ u32 divisor);
unsigned long parent_clk_frequency;
u32 bus_frequency;
/* Transaction state. */
@@ -150,6 +161,8 @@
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;
@@ -227,32 +240,26 @@
}
#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);
@@ -269,34 +276,36 @@
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);
@@ -310,20 +319,18 @@
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 @@
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;
@@ -380,20 +399,16 @@
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;
}
@@ -403,19 +418,29 @@
* 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;
}
@@ -427,14 +452,37 @@
* 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;
@@ -449,14 +497,14 @@
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;
+ /* fall through */
case ASPEED_I2C_MASTER_TX_FIRST:
if (bus->buf_index < msg->len) {
bus->master_state = ASPEED_I2C_MASTER_TX;
@@ -472,13 +520,13 @@
/* RX may not have completed yet (only address cycle) */
if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE))
goto out_no_complete;
- /* fallthrough intended */
+ /* fall through */
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;
@@ -506,11 +554,13 @@
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;
@@ -540,35 +590,66 @@
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);
+ 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);
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,
@@ -576,15 +657,16 @@
{
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)
@@ -604,10 +686,29 @@
time_left = wait_for_completion_timeout(&bus->cmd_complete,
bus->adap.timeout);
- if (time_left == 0)
+ if (time_left == 0) {
+ /*
+ * If timed out and bus is still busy in a multi master
+ * environment, attempt recovery at here.
+ */
+ if (bus->multi_master &&
+ (readl(bus->base + ASPEED_I2C_CMD_REG) &
+ ASPEED_I2CD_BUS_BUSY_STS))
+ aspeed_i2c_recover_bus(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)
@@ -647,7 +748,7 @@
__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;
@@ -686,16 +787,27 @@
#endif /* CONFIG_I2C_SLAVE */
};
-static u32 aspeed_i2c_get_clk_reg_val(u32 clk_high_low_max, u32 divisor)
+static u32 aspeed_i2c_get_clk_reg_val(struct device *dev,
+ u32 clk_high_low_mask,
+ u32 divisor)
{
- u32 base_clk, clk_high, clk_low, tmp;
+ u32 base_clk_divisor, clk_high_low_max, clk_high, clk_low, tmp;
+
+ /*
+ * SCL_high and SCL_low represent a value 1 greater than what is stored
+ * since a zero divider is meaningless. Thus, the max value each can
+ * store is every bit set + 1. Since SCL_high and SCL_low are added
+ * together (see below), the max value of both is the max value of one
+ * them times two.
+ */
+ clk_high_low_max = (clk_high_low_mask + 1) * 2;
/*
* The actual clock frequency of SCL is:
* SCL_freq = APB_freq / (base_freq * (SCL_high + SCL_low))
* = APB_freq / divisor
* where base_freq is a programmable clock divider; its value is
- * base_freq = 1 << base_clk
+ * base_freq = 1 << base_clk_divisor
* SCL_high is the number of base_freq clock cycles that SCL stays high
* and SCL_low is the number of base_freq clock cycles that SCL stays
* low for a period of SCL.
@@ -705,47 +817,59 @@
* SCL_low = clk_low + 1
* Thus,
* SCL_freq = APB_freq /
- * ((1 << base_clk) * (clk_high + 1 + clk_low + 1))
+ * ((1 << base_clk_divisor) * (clk_high + 1 + clk_low + 1))
* The documentation recommends clk_high >= clk_high_max / 2 and
* clk_low >= clk_low_max / 2 - 1 when possible; this last constraint
* gives us the following solution:
*/
- base_clk = divisor > clk_high_low_max ?
+ base_clk_divisor = divisor > clk_high_low_max ?
ilog2((divisor - 1) / clk_high_low_max) + 1 : 0;
- tmp = (divisor + (1 << base_clk) - 1) >> base_clk;
- clk_low = tmp / 2;
- clk_high = tmp - clk_low;
- if (clk_high)
- clk_high--;
+ if (base_clk_divisor > ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) {
+ base_clk_divisor = ASPEED_I2CD_TIME_BASE_DIVISOR_MASK;
+ clk_low = clk_high_low_mask;
+ clk_high = clk_high_low_mask;
+ dev_err(dev,
+ "clamping clock divider: divider requested, %u, is greater than largest possible divider, %u.\n",
+ divisor, (1 << base_clk_divisor) * clk_high_low_max);
+ } else {
+ tmp = (divisor + (1 << base_clk_divisor) - 1)
+ >> base_clk_divisor;
+ clk_low = tmp / 2;
+ clk_high = tmp - clk_low;
- if (clk_low)
- clk_low--;
+ if (clk_high)
+ clk_high--;
+
+ if (clk_low)
+ clk_low--;
+ }
return ((clk_high << ASPEED_I2CD_TIME_SCL_HIGH_SHIFT)
& ASPEED_I2CD_TIME_SCL_HIGH_MASK)
| ((clk_low << ASPEED_I2CD_TIME_SCL_LOW_SHIFT)
& ASPEED_I2CD_TIME_SCL_LOW_MASK)
- | (base_clk & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK);
+ | (base_clk_divisor
+ & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK);
}
-static u32 aspeed_i2c_24xx_get_clk_reg_val(u32 divisor)
+static u32 aspeed_i2c_24xx_get_clk_reg_val(struct device *dev, u32 divisor)
{
/*
* clk_high and clk_low are each 3 bits wide, so each can hold a max
* value of 8 giving a clk_high_low_max of 16.
*/
- return aspeed_i2c_get_clk_reg_val(16, divisor);
+ return aspeed_i2c_get_clk_reg_val(dev, GENMASK(2, 0), divisor);
}
-static u32 aspeed_i2c_25xx_get_clk_reg_val(u32 divisor)
+static u32 aspeed_i2c_25xx_get_clk_reg_val(struct device *dev, u32 divisor)
{
/*
* clk_high and clk_low are each 4 bits wide, so each can hold a max
* value of 16 giving a clk_high_low_max of 32.
*/
- return aspeed_i2c_get_clk_reg_val(32, divisor);
+ return aspeed_i2c_get_clk_reg_val(dev, GENMASK(3, 0), divisor);
}
/* precondition: bus.lock has been acquired. */
@@ -758,7 +882,7 @@
clk_reg_val &= (ASPEED_I2CD_TIME_TBUF_MASK |
ASPEED_I2CD_TIME_THDSTA_MASK |
ASPEED_I2CD_TIME_TACST_MASK);
- clk_reg_val |= bus->get_clk_reg_val(divisor);
+ clk_reg_val |= bus->get_clk_reg_val(bus->dev, divisor);
writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1);
writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2);
@@ -779,7 +903,9 @@
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 */
@@ -874,14 +1000,14 @@
if (!match)
bus->get_clk_reg_val = aspeed_i2c_24xx_get_clk_reg_val;
else
- bus->get_clk_reg_val = (u32 (*)(u32))match->data;
+ bus->get_clk_reg_val = (u32 (*)(struct device *, u32))
+ match->data;
/* Initialize the I2C adapter */
spin_lock_init(&bus->lock);
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;