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-rw-r--r--drivers/i2c/busses/Kconfig12
-rw-r--r--drivers/i2c/busses/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-mv64xxx.c328
-rw-r--r--drivers/i2c/busses/i2c-opal.c294
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c112
5 files changed, 558 insertions, 189 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index c1351d9fb35b..31e8308ba899 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -753,6 +753,7 @@ config I2C_SH7760
config I2C_SH_MOBILE
tristate "SuperH Mobile I2C Controller"
+ depends on HAS_DMA
depends on SUPERH || ARCH_SHMOBILE || COMPILE_TEST
help
If you say yes to this option, support will be included for the
@@ -1072,4 +1073,15 @@ config SCx200_ACB
This support is also available as a module. If so, the module
will be called scx200_acb.
+config I2C_OPAL
+ tristate "IBM OPAL I2C driver"
+ depends on PPC_POWERNV
+ default y
+ help
+ This exposes the PowerNV platform i2c busses to the linux i2c layer,
+ the driver is based on the OPAL interfaces.
+
+ This driver can also be built as a module. If so, the module will be
+ called as i2c-opal.
+
endmenu
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 5e6c8223719e..56388f658d2f 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -102,6 +102,7 @@ obj-$(CONFIG_I2C_ACORN) += i2c-acorn.o
obj-$(CONFIG_I2C_BCM_KONA) += i2c-bcm-kona.o
obj-$(CONFIG_I2C_CROS_EC_TUNNEL) += i2c-cros-ec-tunnel.o
obj-$(CONFIG_I2C_ELEKTOR) += i2c-elektor.o
+obj-$(CONFIG_I2C_OPAL) += i2c-opal.o
obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o
obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index 373f6d4e4080..30059c1df2a3 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -30,12 +30,12 @@
#define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7)
#define MV64XXX_I2C_BAUD_DIV_M(val) ((val & 0xf) << 3)
-#define MV64XXX_I2C_REG_CONTROL_ACK 0x00000004
-#define MV64XXX_I2C_REG_CONTROL_IFLG 0x00000008
-#define MV64XXX_I2C_REG_CONTROL_STOP 0x00000010
-#define MV64XXX_I2C_REG_CONTROL_START 0x00000020
-#define MV64XXX_I2C_REG_CONTROL_TWSIEN 0x00000040
-#define MV64XXX_I2C_REG_CONTROL_INTEN 0x00000080
+#define MV64XXX_I2C_REG_CONTROL_ACK BIT(2)
+#define MV64XXX_I2C_REG_CONTROL_IFLG BIT(3)
+#define MV64XXX_I2C_REG_CONTROL_STOP BIT(4)
+#define MV64XXX_I2C_REG_CONTROL_START BIT(5)
+#define MV64XXX_I2C_REG_CONTROL_TWSIEN BIT(6)
+#define MV64XXX_I2C_REG_CONTROL_INTEN BIT(7)
/* Ctlr status values */
#define MV64XXX_I2C_STATUS_BUS_ERR 0x00
@@ -68,19 +68,17 @@
#define MV64XXX_I2C_REG_BRIDGE_TIMING 0xe0
/* Bridge Control values */
-#define MV64XXX_I2C_BRIDGE_CONTROL_WR 0x00000001
-#define MV64XXX_I2C_BRIDGE_CONTROL_RD 0x00000002
+#define MV64XXX_I2C_BRIDGE_CONTROL_WR BIT(0)
+#define MV64XXX_I2C_BRIDGE_CONTROL_RD BIT(1)
#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT 2
-#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT 0x00001000
+#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT BIT(12)
#define MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT 13
#define MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT 16
-#define MV64XXX_I2C_BRIDGE_CONTROL_ENABLE 0x00080000
+#define MV64XXX_I2C_BRIDGE_CONTROL_ENABLE BIT(19)
+#define MV64XXX_I2C_BRIDGE_CONTROL_REPEATED_START BIT(20)
/* Bridge Status values */
-#define MV64XXX_I2C_BRIDGE_STATUS_ERROR 0x00000001
-#define MV64XXX_I2C_STATUS_OFFLOAD_ERROR 0xf0000001
-#define MV64XXX_I2C_STATUS_OFFLOAD_OK 0xf0000000
-
+#define MV64XXX_I2C_BRIDGE_STATUS_ERROR BIT(0)
/* Driver states */
enum {
@@ -99,14 +97,12 @@ enum {
MV64XXX_I2C_ACTION_INVALID,
MV64XXX_I2C_ACTION_CONTINUE,
MV64XXX_I2C_ACTION_SEND_RESTART,
- MV64XXX_I2C_ACTION_OFFLOAD_RESTART,
MV64XXX_I2C_ACTION_SEND_ADDR_1,
MV64XXX_I2C_ACTION_SEND_ADDR_2,
MV64XXX_I2C_ACTION_SEND_DATA,
MV64XXX_I2C_ACTION_RCV_DATA,
MV64XXX_I2C_ACTION_RCV_DATA_STOP,
MV64XXX_I2C_ACTION_SEND_STOP,
- MV64XXX_I2C_ACTION_OFFLOAD_SEND_STOP,
};
struct mv64xxx_i2c_regs {
@@ -193,75 +189,6 @@ mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
}
}
-static int mv64xxx_i2c_offload_msg(struct mv64xxx_i2c_data *drv_data)
-{
- unsigned long data_reg_hi = 0;
- unsigned long data_reg_lo = 0;
- unsigned long ctrl_reg;
- struct i2c_msg *msg = drv_data->msgs;
-
- if (!drv_data->offload_enabled)
- return -EOPNOTSUPP;
-
- /* Only regular transactions can be offloaded */
- if ((msg->flags & ~(I2C_M_TEN | I2C_M_RD)) != 0)
- return -EINVAL;
-
- /* Only 1-8 byte transfers can be offloaded */
- if (msg->len < 1 || msg->len > 8)
- return -EINVAL;
-
- /* Build transaction */
- ctrl_reg = MV64XXX_I2C_BRIDGE_CONTROL_ENABLE |
- (msg->addr << MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT);
-
- if ((msg->flags & I2C_M_TEN) != 0)
- ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT;
-
- if ((msg->flags & I2C_M_RD) == 0) {
- u8 local_buf[8] = { 0 };
-
- memcpy(local_buf, msg->buf, msg->len);
- data_reg_lo = cpu_to_le32(*((u32 *)local_buf));
- data_reg_hi = cpu_to_le32(*((u32 *)(local_buf+4)));
-
- ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_WR |
- (msg->len - 1) << MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT;
-
- writel(data_reg_lo,
- drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_LO);
- writel(data_reg_hi,
- drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_HI);
-
- } else {
- ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_RD |
- (msg->len - 1) << MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT;
- }
-
- /* Execute transaction */
- writel(ctrl_reg, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL);
-
- return 0;
-}
-
-static void
-mv64xxx_i2c_update_offload_data(struct mv64xxx_i2c_data *drv_data)
-{
- struct i2c_msg *msg = drv_data->msg;
-
- if (msg->flags & I2C_M_RD) {
- u32 data_reg_lo = readl(drv_data->reg_base +
- MV64XXX_I2C_REG_RX_DATA_LO);
- u32 data_reg_hi = readl(drv_data->reg_base +
- MV64XXX_I2C_REG_RX_DATA_HI);
- u8 local_buf[8] = { 0 };
-
- *((u32 *)local_buf) = le32_to_cpu(data_reg_lo);
- *((u32 *)(local_buf+4)) = le32_to_cpu(data_reg_hi);
- memcpy(msg->buf, local_buf, msg->len);
- }
-
-}
/*
*****************************************************************************
*
@@ -389,16 +316,6 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
drv_data->rc = -ENXIO;
break;
- case MV64XXX_I2C_STATUS_OFFLOAD_OK:
- if (drv_data->send_stop || drv_data->aborting) {
- drv_data->action = MV64XXX_I2C_ACTION_OFFLOAD_SEND_STOP;
- drv_data->state = MV64XXX_I2C_STATE_IDLE;
- } else {
- drv_data->action = MV64XXX_I2C_ACTION_OFFLOAD_RESTART;
- drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_RESTART;
- }
- break;
-
default:
dev_err(&drv_data->adapter.dev,
"mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, "
@@ -419,25 +336,15 @@ static void mv64xxx_i2c_send_start(struct mv64xxx_i2c_data *drv_data)
drv_data->aborting = 0;
drv_data->rc = 0;
- /* Can we offload this msg ? */
- if (mv64xxx_i2c_offload_msg(drv_data) < 0) {
- /* No, switch to standard path */
- mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs);
- writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START,
- drv_data->reg_base + drv_data->reg_offsets.control);
- }
+ mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs);
+ writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START,
+ drv_data->reg_base + drv_data->reg_offsets.control);
}
static void
mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
{
switch(drv_data->action) {
- case MV64XXX_I2C_ACTION_OFFLOAD_RESTART:
- mv64xxx_i2c_update_offload_data(drv_data);
- writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL);
- writel(0, drv_data->reg_base +
- MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE);
- /* FALLTHRU */
case MV64XXX_I2C_ACTION_SEND_RESTART:
/* We should only get here if we have further messages */
BUG_ON(drv_data->num_msgs == 0);
@@ -518,16 +425,71 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
drv_data->block = 0;
wake_up(&drv_data->waitq);
break;
+ }
+}
- case MV64XXX_I2C_ACTION_OFFLOAD_SEND_STOP:
- mv64xxx_i2c_update_offload_data(drv_data);
- writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL);
- writel(0, drv_data->reg_base +
- MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE);
- drv_data->block = 0;
- wake_up(&drv_data->waitq);
- break;
+static void
+mv64xxx_i2c_read_offload_rx_data(struct mv64xxx_i2c_data *drv_data,
+ struct i2c_msg *msg)
+{
+ u32 buf[2];
+
+ buf[0] = readl(drv_data->reg_base + MV64XXX_I2C_REG_RX_DATA_LO);
+ buf[1] = readl(drv_data->reg_base + MV64XXX_I2C_REG_RX_DATA_HI);
+
+ memcpy(msg->buf, buf, msg->len);
+}
+
+static int
+mv64xxx_i2c_intr_offload(struct mv64xxx_i2c_data *drv_data)
+{
+ u32 cause, status;
+
+ cause = readl(drv_data->reg_base +
+ MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE);
+ if (!cause)
+ return IRQ_NONE;
+
+ status = readl(drv_data->reg_base +
+ MV64XXX_I2C_REG_BRIDGE_STATUS);
+
+ if (status & MV64XXX_I2C_BRIDGE_STATUS_ERROR) {
+ drv_data->rc = -EIO;
+ goto out;
+ }
+
+ drv_data->rc = 0;
+
+ /*
+ * Transaction is a one message read transaction, read data
+ * for this message.
+ */
+ if (drv_data->num_msgs == 1 && drv_data->msgs[0].flags & I2C_M_RD) {
+ mv64xxx_i2c_read_offload_rx_data(drv_data, drv_data->msgs);
+ drv_data->msgs++;
+ drv_data->num_msgs--;
+ }
+ /*
+ * Transaction is a two messages write/read transaction, read
+ * data for the second (read) message.
+ */
+ else if (drv_data->num_msgs == 2 &&
+ !(drv_data->msgs[0].flags & I2C_M_RD) &&
+ drv_data->msgs[1].flags & I2C_M_RD) {
+ mv64xxx_i2c_read_offload_rx_data(drv_data, drv_data->msgs + 1);
+ drv_data->msgs += 2;
+ drv_data->num_msgs -= 2;
}
+
+out:
+ writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL);
+ writel(0, drv_data->reg_base +
+ MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE);
+ drv_data->block = 0;
+
+ wake_up(&drv_data->waitq);
+
+ return IRQ_HANDLED;
}
static irqreturn_t
@@ -540,20 +502,9 @@ mv64xxx_i2c_intr(int irq, void *dev_id)
spin_lock_irqsave(&drv_data->lock, flags);
- if (drv_data->offload_enabled) {
- while (readl(drv_data->reg_base +
- MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE)) {
- int reg_status = readl(drv_data->reg_base +
- MV64XXX_I2C_REG_BRIDGE_STATUS);
- if (reg_status & MV64XXX_I2C_BRIDGE_STATUS_ERROR)
- status = MV64XXX_I2C_STATUS_OFFLOAD_ERROR;
- else
- status = MV64XXX_I2C_STATUS_OFFLOAD_OK;
- mv64xxx_i2c_fsm(drv_data, status);
- mv64xxx_i2c_do_action(drv_data);
- rc = IRQ_HANDLED;
- }
- }
+ if (drv_data->offload_enabled)
+ rc = mv64xxx_i2c_intr_offload(drv_data);
+
while (readl(drv_data->reg_base + drv_data->reg_offsets.control) &
MV64XXX_I2C_REG_CONTROL_IFLG) {
status = readl(drv_data->reg_base + drv_data->reg_offsets.status);
@@ -635,6 +586,117 @@ mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg,
return drv_data->rc;
}
+static void
+mv64xxx_i2c_prepare_tx(struct mv64xxx_i2c_data *drv_data)
+{
+ struct i2c_msg *msg = drv_data->msgs;
+ u32 buf[2];
+
+ memcpy(buf, msg->buf, msg->len);
+
+ writel(buf[0], drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_LO);
+ writel(buf[1], drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_HI);
+}
+
+static int
+mv64xxx_i2c_offload_xfer(struct mv64xxx_i2c_data *drv_data)
+{
+ struct i2c_msg *msgs = drv_data->msgs;
+ int num = drv_data->num_msgs;
+ unsigned long ctrl_reg;
+ unsigned long flags;
+
+ spin_lock_irqsave(&drv_data->lock, flags);
+
+ /* Build transaction */
+ ctrl_reg = MV64XXX_I2C_BRIDGE_CONTROL_ENABLE |
+ (msgs[0].addr << MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT);
+
+ if (msgs[0].flags & I2C_M_TEN)
+ ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT;
+
+ /* Single write message transaction */
+ if (num == 1 && !(msgs[0].flags & I2C_M_RD)) {
+ size_t len = msgs[0].len - 1;
+
+ ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_WR |
+ (len << MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT);
+ mv64xxx_i2c_prepare_tx(drv_data);
+ }
+ /* Single read message transaction */
+ else if (num == 1 && msgs[0].flags & I2C_M_RD) {
+ size_t len = msgs[0].len - 1;
+
+ ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_RD |
+ (len << MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT);
+ }
+ /*
+ * Transaction with one write and one read message. This is
+ * guaranteed by the mv64xx_i2c_can_offload() checks.
+ */
+ else if (num == 2) {
+ size_t lentx = msgs[0].len - 1;
+ size_t lenrx = msgs[1].len - 1;
+
+ ctrl_reg |=
+ MV64XXX_I2C_BRIDGE_CONTROL_RD |
+ MV64XXX_I2C_BRIDGE_CONTROL_WR |
+ (lentx << MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT) |
+ (lenrx << MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT) |
+ MV64XXX_I2C_BRIDGE_CONTROL_REPEATED_START;
+ mv64xxx_i2c_prepare_tx(drv_data);
+ }
+
+ /* Execute transaction */
+ drv_data->block = 1;
+ writel(ctrl_reg, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL);
+ spin_unlock_irqrestore(&drv_data->lock, flags);
+
+ mv64xxx_i2c_wait_for_completion(drv_data);
+
+ return drv_data->rc;
+}
+
+static bool
+mv64xxx_i2c_valid_offload_sz(struct i2c_msg *msg)
+{
+ return msg->len <= 8 && msg->len >= 1;
+}
+
+static bool
+mv64xxx_i2c_can_offload(struct mv64xxx_i2c_data *drv_data)
+{
+ struct i2c_msg *msgs = drv_data->msgs;
+ int num = drv_data->num_msgs;
+
+ return false;
+
+ if (!drv_data->offload_enabled)
+ return false;
+
+ /*
+ * We can offload a transaction consisting of a single
+ * message, as long as the message has a length between 1 and
+ * 8 bytes.
+ */
+ if (num == 1 && mv64xxx_i2c_valid_offload_sz(msgs))
+ return true;
+
+ /*
+ * We can offload a transaction consisting of two messages, if
+ * the first is a write and a second is a read, and both have
+ * a length between 1 and 8 bytes.
+ */
+ if (num == 2 &&
+ mv64xxx_i2c_valid_offload_sz(msgs) &&
+ mv64xxx_i2c_valid_offload_sz(msgs + 1) &&
+ !(msgs[0].flags & I2C_M_RD) &&
+ msgs[1].flags & I2C_M_RD)
+ return true;
+
+ return false;
+}
+
/*
*****************************************************************************
*
@@ -658,7 +720,11 @@ mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
drv_data->msgs = msgs;
drv_data->num_msgs = num;
- rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[0], num == 1);
+ if (mv64xxx_i2c_can_offload(drv_data))
+ rc = mv64xxx_i2c_offload_xfer(drv_data);
+ else
+ rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[0], num == 1);
+
if (rc < 0)
ret = rc;
diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c
new file mode 100644
index 000000000000..16f90b1a7508
--- /dev/null
+++ b/drivers/i2c/busses/i2c-opal.c
@@ -0,0 +1,294 @@
+/*
+ * IBM OPAL I2C driver
+ * Copyright (C) 2014 IBM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <asm/firmware.h>
+#include <asm/opal.h>
+
+static int i2c_opal_translate_error(int rc)
+{
+ switch (rc) {
+ case OPAL_NO_MEM:
+ return -ENOMEM;
+ case OPAL_PARAMETER:
+ return -EINVAL;
+ case OPAL_I2C_ARBT_LOST:
+ return -EAGAIN;
+ case OPAL_I2C_TIMEOUT:
+ return -ETIMEDOUT;
+ case OPAL_I2C_NACK_RCVD:
+ return -ENXIO;
+ case OPAL_I2C_STOP_ERR:
+ return -EBUSY;
+ default:
+ return -EIO;
+ }
+}
+
+static int i2c_opal_send_request(u32 bus_id, struct opal_i2c_request *req)
+{
+ struct opal_msg msg;
+ int token, rc;
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ if (token != -ERESTARTSYS)
+ pr_err("Failed to get the async token\n");
+
+ return token;
+ }
+
+ rc = opal_i2c_request(token, bus_id, req);
+ if (rc != OPAL_ASYNC_COMPLETION) {
+ rc = i2c_opal_translate_error(rc);
+ goto exit;
+ }
+
+ rc = opal_async_wait_response(token, &msg);
+ if (rc)
+ goto exit;
+
+ rc = be64_to_cpu(msg.params[1]);
+ if (rc != OPAL_SUCCESS) {
+ rc = i2c_opal_translate_error(rc);
+ goto exit;
+ }
+
+exit:
+ opal_async_release_token(token);
+ return rc;
+}
+
+static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+ int num)
+{
+ unsigned long opal_id = (unsigned long)adap->algo_data;
+ struct opal_i2c_request req;
+ int rc, i;
+
+ /* We only support fairly simple combinations here of one
+ * or two messages
+ */
+ memset(&req, 0, sizeof(req));
+ switch(num) {
+ case 0:
+ return 0;
+ case 1:
+ req.type = (msgs[0].flags & I2C_M_RD) ?
+ OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE;
+ req.addr = cpu_to_be16(msgs[0].addr);
+ req.size = cpu_to_be32(msgs[0].len);
+ req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf));
+ break;
+ case 2:
+ /* For two messages, we basically support only simple
+ * smbus transactions of a write plus a read. We might
+ * want to allow also two writes but we'd have to bounce
+ * the data into a single buffer.
+ */
+ if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD))
+ return -EOPNOTSUPP;
+ if (msgs[0].len > 4)
+ return -EOPNOTSUPP;
+ if (msgs[0].addr != msgs[1].addr)
+ return -EOPNOTSUPP;
+ req.type = OPAL_I2C_SM_READ;
+ req.addr = cpu_to_be16(msgs[0].addr);
+ req.subaddr_sz = msgs[0].len;
+ for (i = 0; i < msgs[0].len; i++)
+ req.subaddr = (req.subaddr << 8) | msgs[0].buf[i];
+ req.subaddr = cpu_to_be32(req.subaddr);
+ req.size = cpu_to_be32(msgs[1].len);
+ req.buffer_ra = cpu_to_be64(__pa(msgs[1].buf));
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ rc = i2c_opal_send_request(opal_id, &req);
+ if (rc)
+ return rc;
+
+ return num;
+}
+
+static int i2c_opal_smbus_xfer(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write,
+ u8 command, int size, union i2c_smbus_data *data)
+{
+ unsigned long opal_id = (unsigned long)adap->algo_data;
+ struct opal_i2c_request req;
+ u8 local[2];
+ int rc;
+
+ memset(&req, 0, sizeof(req));
+
+ req.addr = cpu_to_be16(addr);
+ switch (size) {
+ case I2C_SMBUS_BYTE:
+ req.buffer_ra = cpu_to_be64(__pa(&data->byte));
+ req.size = cpu_to_be32(1);
+ /* Fall through */
+ case I2C_SMBUS_QUICK:
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE;
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ req.buffer_ra = cpu_to_be64(__pa(&data->byte));
+ req.size = cpu_to_be32(1);
+ req.subaddr = cpu_to_be32(command);
+ req.subaddr_sz = 1;
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ if (!read_write) {
+ local[0] = data->word & 0xff;
+ local[1] = (data->word >> 8) & 0xff;
+ }
+ req.buffer_ra = cpu_to_be64(__pa(local));
+ req.size = cpu_to_be32(2);
+ req.subaddr = cpu_to_be32(command);
+ req.subaddr_sz = 1;
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
+ break;
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ req.buffer_ra = cpu_to_be64(__pa(&data->block[1]));
+ req.size = cpu_to_be32(data->block[0]);
+ req.subaddr = cpu_to_be32(command);
+ req.subaddr_sz = 1;
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ rc = i2c_opal_send_request(opal_id, &req);
+ if (!rc && read_write && size == I2C_SMBUS_WORD_DATA) {
+ data->word = ((u16)local[1]) << 8;
+ data->word |= local[0];
+ }
+
+ return rc;
+}
+
+static u32 i2c_opal_func(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_I2C_BLOCK;
+}
+
+static const struct i2c_algorithm i2c_opal_algo = {
+ .master_xfer = i2c_opal_master_xfer,
+ .smbus_xfer = i2c_opal_smbus_xfer,
+ .functionality = i2c_opal_func,
+};
+
+static int i2c_opal_probe(struct platform_device *pdev)
+{
+ struct i2c_adapter *adapter;
+ const char *pname;
+ u32 opal_id;
+ int rc;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ rc = of_property_read_u32(pdev->dev.of_node, "ibm,opal-id", &opal_id);
+ if (rc) {
+ dev_err(&pdev->dev, "Missing ibm,opal-id property !\n");
+ return -EIO;
+ }
+
+ adapter = devm_kzalloc(&pdev->dev, sizeof(*adapter), GFP_KERNEL);
+ if (!adapter)
+ return -ENOMEM;
+
+ adapter->algo = &i2c_opal_algo;
+ adapter->algo_data = (void *)(unsigned long)opal_id;
+ adapter->dev.parent = &pdev->dev;
+ adapter->dev.of_node = of_node_get(pdev->dev.of_node);
+ pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);
+ if (pname)
+ strlcpy(adapter->name, pname, sizeof(adapter->name));
+ else
+ strlcpy(adapter->name, "opal", sizeof(adapter->name));
+
+ platform_set_drvdata(pdev, adapter);
+ rc = i2c_add_adapter(adapter);
+ if (rc)
+ dev_err(&pdev->dev, "Failed to register the i2c adapter\n");
+
+ return rc;
+}
+
+static int i2c_opal_remove(struct platform_device *pdev)
+{
+ struct i2c_adapter *adapter = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(adapter);
+
+ return 0;
+}
+
+static const struct of_device_id i2c_opal_of_match[] = {
+ {
+ .compatible = "ibm,opal-i2c",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, i2c_opal_of_match);
+
+static struct platform_driver i2c_opal_driver = {
+ .probe = i2c_opal_probe,
+ .remove = i2c_opal_remove,
+ .driver = {
+ .name = "i2c-opal",
+ .of_match_table = i2c_opal_of_match,
+ },
+};
+
+static int __init i2c_opal_init(void)
+{
+ if (!firmware_has_feature(FW_FEATURE_OPAL))
+ return -ENODEV;
+
+ return platform_driver_register(&i2c_opal_driver);
+}
+module_init(i2c_opal_init);
+
+static void __exit i2c_opal_exit(void)
+{
+ return platform_driver_unregister(&i2c_opal_driver);
+}
+module_exit(i2c_opal_exit);
+
+MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("IBM OPAL I2C driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index d7efaf44868b..440d5dbc8b5f 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -140,6 +140,7 @@ struct sh_mobile_i2c_data {
int sr;
bool send_stop;
+ struct resource *res;
struct dma_chan *dma_tx;
struct dma_chan *dma_rx;
struct scatterlist sg;
@@ -539,6 +540,42 @@ static void sh_mobile_i2c_dma_callback(void *data)
iic_set_clr(pd, ICIC, 0, ICIC_TDMAE | ICIC_RDMAE);
}
+static struct dma_chan *sh_mobile_i2c_request_dma_chan(struct device *dev,
+ enum dma_transfer_direction dir, dma_addr_t port_addr)
+{
+ struct dma_chan *chan;
+ struct dma_slave_config cfg;
+ char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx";
+ int ret;
+
+ chan = dma_request_slave_channel_reason(dev, chan_name);
+ if (IS_ERR(chan)) {
+ ret = PTR_ERR(chan);
+ dev_dbg(dev, "request_channel failed for %s (%d)\n", chan_name, ret);
+ return chan;
+ }
+
+ memset(&cfg, 0, sizeof(cfg));
+ cfg.direction = dir;
+ if (dir == DMA_MEM_TO_DEV) {
+ cfg.dst_addr = port_addr;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ } else {
+ cfg.src_addr = port_addr;
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ }
+
+ ret = dmaengine_slave_config(chan, &cfg);
+ if (ret) {
+ dev_dbg(dev, "slave_config failed for %s (%d)\n", chan_name, ret);
+ dma_release_channel(chan);
+ return ERR_PTR(ret);
+ }
+
+ dev_dbg(dev, "got DMA channel for %s\n", chan_name);
+ return chan;
+}
+
static void sh_mobile_i2c_xfer_dma(struct sh_mobile_i2c_data *pd)
{
bool read = pd->msg->flags & I2C_M_RD;
@@ -548,7 +585,16 @@ static void sh_mobile_i2c_xfer_dma(struct sh_mobile_i2c_data *pd)
dma_addr_t dma_addr;
dma_cookie_t cookie;
- if (!chan)
+ if (PTR_ERR(chan) == -EPROBE_DEFER) {
+ if (read)
+ chan = pd->dma_rx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_DEV_TO_MEM,
+ pd->res->start + ICDR);
+ else
+ chan = pd->dma_tx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_MEM_TO_DEV,
+ pd->res->start + ICDR);
+ }
+
+ if (IS_ERR(chan))
return;
dma_addr = dma_map_single(chan->device->dev, pd->msg->buf, pd->msg->len, dir);
@@ -747,56 +793,16 @@ static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids);
-static int sh_mobile_i2c_request_dma_chan(struct device *dev, enum dma_transfer_direction dir,
- dma_addr_t port_addr, struct dma_chan **chan_ptr)
-{
- struct dma_chan *chan;
- struct dma_slave_config cfg;
- char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx";
- int ret;
-
- *chan_ptr = NULL;
-
- chan = dma_request_slave_channel_reason(dev, chan_name);
- if (IS_ERR(chan)) {
- ret = PTR_ERR(chan);
- dev_dbg(dev, "request_channel failed for %s (%d)\n", chan_name, ret);
- return ret;
- }
-
- memset(&cfg, 0, sizeof(cfg));
- cfg.direction = dir;
- if (dir == DMA_MEM_TO_DEV) {
- cfg.dst_addr = port_addr;
- cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
- } else {
- cfg.src_addr = port_addr;
- cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
- }
-
- ret = dmaengine_slave_config(chan, &cfg);
- if (ret) {
- dev_dbg(dev, "slave_config failed for %s (%d)\n", chan_name, ret);
- dma_release_channel(chan);
- return ret;
- }
-
- *chan_ptr = chan;
-
- dev_dbg(dev, "got DMA channel for %s\n", chan_name);
- return 0;
-}
-
static void sh_mobile_i2c_release_dma(struct sh_mobile_i2c_data *pd)
{
- if (pd->dma_tx) {
+ if (!IS_ERR(pd->dma_tx)) {
dma_release_channel(pd->dma_tx);
- pd->dma_tx = NULL;
+ pd->dma_tx = ERR_PTR(-EPROBE_DEFER);
}
- if (pd->dma_rx) {
+ if (!IS_ERR(pd->dma_rx)) {
dma_release_channel(pd->dma_rx);
- pd->dma_rx = NULL;
+ pd->dma_rx = ERR_PTR(-EPROBE_DEFER);
}
}
@@ -849,6 +855,7 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ pd->res = res;
pd->reg = devm_ioremap_resource(&dev->dev, res);
if (IS_ERR(pd->reg))
return PTR_ERR(pd->reg);
@@ -889,17 +896,7 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
/* Init DMA */
sg_init_table(&pd->sg, 1);
pd->dma_direction = DMA_NONE;
- ret = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_DEV_TO_MEM,
- res->start + ICDR, &pd->dma_rx);
- if (ret == -EPROBE_DEFER)
- return ret;
-
- ret = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_MEM_TO_DEV,
- res->start + ICDR, &pd->dma_tx);
- if (ret == -EPROBE_DEFER) {
- sh_mobile_i2c_release_dma(pd);
- return ret;
- }
+ pd->dma_rx = pd->dma_tx = ERR_PTR(-EPROBE_DEFER);
/* Enable Runtime PM for this device.
*
@@ -937,8 +934,7 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
return ret;
}
- dev_info(&dev->dev, "I2C adapter %d, bus speed %lu Hz, DMA=%c\n",
- adap->nr, pd->bus_speed, (pd->dma_rx || pd->dma_tx) ? 'y' : 'n');
+ dev_info(&dev->dev, "I2C adapter %d, bus speed %lu Hz\n", adap->nr, pd->bus_speed);
return 0;
}
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