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* [PATCH v2 0/2] platform/chrome: Add support for mec1322 EC
@ 2016-12-02 15:35 Thierry Escande
  2016-12-02 15:35 ` [PATCH v2 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Thierry Escande @ 2016-12-02 15:35 UTC (permalink / raw)
  To: Benson Leung; +Cc: linux-kernel

Hi Benson,

This series adds support for the LPC Microchip Embedded Controller 1322.

v2:
-Add a few lines in Kconfig description
-Fixed coding style issues
-Updated copyright to year 2016

Shawn Nematbakhsh (2):
  platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants
  platform/chrome: cros_ec_lpc: Add support for mec1322 EC

 drivers/platform/chrome/Kconfig           |  12 +++
 drivers/platform/chrome/Makefile          |   4 +-
 drivers/platform/chrome/cros_ec_lpc.c     |  93 +++++++++-----------
 drivers/platform/chrome/cros_ec_lpc_mec.c | 140 ++++++++++++++++++++++++++++++
 drivers/platform/chrome/cros_ec_lpc_reg.c | 133 ++++++++++++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_mec.h       |  90 +++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_reg.h       |  61 +++++++++++++
 7 files changed, 482 insertions(+), 51 deletions(-)
 create mode 100644 drivers/platform/chrome/cros_ec_lpc_mec.c
 create mode 100644 drivers/platform/chrome/cros_ec_lpc_reg.c
 create mode 100644 include/linux/mfd/cros_ec_lpc_mec.h
 create mode 100644 include/linux/mfd/cros_ec_lpc_reg.h

-- 
2.7.4

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH v2 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants
  2016-12-02 15:35 [PATCH v2 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
@ 2016-12-02 15:35 ` Thierry Escande
  2016-12-02 15:35 ` [PATCH v2 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
  2016-12-02 15:39 ` [PATCH v2 0/2] platform/chrome: " Benson Leung
  2 siblings, 0 replies; 4+ messages in thread
From: Thierry Escande @ 2016-12-02 15:35 UTC (permalink / raw)
  To: Benson Leung; +Cc: linux-kernel

From: Shawn Nematbakhsh <shawnn@chromium.org>

Call common functions for read / write to prepare support for future
LPC protocol variants which use different I/O ops than inb / outb.

Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
---
 drivers/platform/chrome/Makefile          |  3 +-
 drivers/platform/chrome/cros_ec_lpc.c     | 88 +++++++++++++------------------
 drivers/platform/chrome/cros_ec_lpc_reg.c | 64 ++++++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_reg.h       | 47 +++++++++++++++++
 4 files changed, 151 insertions(+), 51 deletions(-)
 create mode 100644 drivers/platform/chrome/cros_ec_lpc_reg.c
 create mode 100644 include/linux/mfd/cros_ec_lpc_reg.h

diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 4f34627..127fbe8 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_CHROMEOS_PSTORE)		+= chromeos_pstore.o
 cros_ec_devs-objs			:= cros_ec_dev.o cros_ec_sysfs.o \
 					   cros_ec_lightbar.o cros_ec_vbc.o
 obj-$(CONFIG_CROS_EC_CHARDEV)		+= cros_ec_devs.o
-obj-$(CONFIG_CROS_EC_LPC)		+= cros_ec_lpc.o
+cros_ec_lpcs-objs			:= cros_ec_lpc.o cros_ec_lpc_reg.o
+obj-$(CONFIG_CROS_EC_LPC)		+= cros_ec_lpcs.o
 obj-$(CONFIG_CROS_EC_PROTO)		+= cros_ec_proto.o
 obj-$(CONFIG_CROS_KBD_LED_BACKLIGHT)	+= cros_kbd_led_backlight.o
diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c
index f9a2454..6a782a6 100644
--- a/drivers/platform/chrome/cros_ec_lpc.c
+++ b/drivers/platform/chrome/cros_ec_lpc.c
@@ -26,19 +26,22 @@
 #include <linux/io.h>
 #include <linux/mfd/cros_ec.h>
 #include <linux/mfd/cros_ec_commands.h>
+#include <linux/mfd/cros_ec_lpc_reg.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/printk.h>
 
-#define DRV_NAME "cros_ec_lpc"
+#define DRV_NAME "cros_ec_lpcs"
 
 static int ec_response_timed_out(void)
 {
 	unsigned long one_second = jiffies + HZ;
+	u8 data;
 
 	usleep_range(200, 300);
 	do {
-		if (!(inb(EC_LPC_ADDR_HOST_CMD) & EC_LPC_STATUS_BUSY_MASK))
+		if (!(cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_CMD, 1, &data) &
+		    EC_LPC_STATUS_BUSY_MASK))
 			return 0;
 		usleep_range(100, 200);
 	} while (time_before(jiffies, one_second));
@@ -51,21 +54,20 @@ static int cros_ec_pkt_xfer_lpc(struct cros_ec_device *ec,
 {
 	struct ec_host_request *request;
 	struct ec_host_response response;
-	u8 sum = 0;
-	int i;
+	u8 sum;
 	int ret = 0;
 	u8 *dout;
 
 	ret = cros_ec_prepare_tx(ec, msg);
 
 	/* Write buffer */
-	for (i = 0; i < ret; i++)
-		outb(ec->dout[i], EC_LPC_ADDR_HOST_PACKET + i);
+	cros_ec_lpc_write_bytes(EC_LPC_ADDR_HOST_PACKET, ret, ec->dout);
 
 	request = (struct ec_host_request *)ec->dout;
 
 	/* Here we go */
-	outb(EC_COMMAND_PROTOCOL_3, EC_LPC_ADDR_HOST_CMD);
+	sum = EC_COMMAND_PROTOCOL_3;
+	cros_ec_lpc_write_bytes(EC_LPC_ADDR_HOST_CMD, 1, &sum);
 
 	if (ec_response_timed_out()) {
 		dev_warn(ec->dev, "EC responsed timed out\n");
@@ -74,17 +76,15 @@ static int cros_ec_pkt_xfer_lpc(struct cros_ec_device *ec,
 	}
 
 	/* Check result */
-	msg->result = inb(EC_LPC_ADDR_HOST_DATA);
+	msg->result = cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_DATA, 1, &sum);
 	ret = cros_ec_check_result(ec, msg);
 	if (ret)
 		goto done;
 
 	/* Read back response */
 	dout = (u8 *)&response;
-	for (i = 0; i < sizeof(response); i++) {
-		dout[i] = inb(EC_LPC_ADDR_HOST_PACKET + i);
-		sum += dout[i];
-	}
+	sum = cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_PACKET, sizeof(response),
+				     dout);
 
 	msg->result = response.result;
 
@@ -97,11 +97,9 @@ static int cros_ec_pkt_xfer_lpc(struct cros_ec_device *ec,
 	}
 
 	/* Read response and process checksum */
-	for (i = 0; i < response.data_len; i++) {
-		msg->data[i] =
-			inb(EC_LPC_ADDR_HOST_PACKET + sizeof(response) + i);
-		sum += msg->data[i];
-	}
+	sum += cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_PACKET +
+				      sizeof(response), response.data_len,
+				      msg->data);
 
 	if (sum) {
 		dev_err(ec->dev,
@@ -121,8 +119,7 @@ static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
 				struct cros_ec_command *msg)
 {
 	struct ec_lpc_host_args args;
-	int csum;
-	int i;
+	u8 sum;
 	int ret = 0;
 
 	if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE ||
@@ -139,24 +136,20 @@ static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
 	args.data_size = msg->outsize;
 
 	/* Initialize checksum */
-	csum = msg->command + args.flags +
-		args.command_version + args.data_size;
+	sum = msg->command + args.flags + args.command_version + args.data_size;
 
 	/* Copy data and update checksum */
-	for (i = 0; i < msg->outsize; i++) {
-		outb(msg->data[i], EC_LPC_ADDR_HOST_PARAM + i);
-		csum += msg->data[i];
-	}
+	sum += cros_ec_lpc_write_bytes(EC_LPC_ADDR_HOST_PARAM, msg->outsize,
+				       msg->data);
 
 	/* Finalize checksum and write args */
-	args.checksum = csum & 0xFF;
-	outb(args.flags, EC_LPC_ADDR_HOST_ARGS);
-	outb(args.command_version, EC_LPC_ADDR_HOST_ARGS + 1);
-	outb(args.data_size, EC_LPC_ADDR_HOST_ARGS + 2);
-	outb(args.checksum, EC_LPC_ADDR_HOST_ARGS + 3);
+	args.checksum = sum;
+	cros_ec_lpc_write_bytes(EC_LPC_ADDR_HOST_ARGS, sizeof(args),
+				(u8 *)&args);
 
 	/* Here we go */
-	outb(msg->command, EC_LPC_ADDR_HOST_CMD);
+	sum = msg->command;
+	cros_ec_lpc_write_bytes(EC_LPC_ADDR_HOST_CMD, 1, &sum);
 
 	if (ec_response_timed_out()) {
 		dev_warn(ec->dev, "EC responsed timed out\n");
@@ -165,16 +158,14 @@ static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
 	}
 
 	/* Check result */
-	msg->result = inb(EC_LPC_ADDR_HOST_DATA);
+	msg->result = cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_DATA, 1, &sum);
 	ret = cros_ec_check_result(ec, msg);
 	if (ret)
 		goto done;
 
 	/* Read back args */
-	args.flags = inb(EC_LPC_ADDR_HOST_ARGS);
-	args.command_version = inb(EC_LPC_ADDR_HOST_ARGS + 1);
-	args.data_size = inb(EC_LPC_ADDR_HOST_ARGS + 2);
-	args.checksum = inb(EC_LPC_ADDR_HOST_ARGS + 3);
+	cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_ARGS, sizeof(args),
+			       (u8 *)&args);
 
 	if (args.data_size > msg->insize) {
 		dev_err(ec->dev,
@@ -185,20 +176,17 @@ static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
 	}
 
 	/* Start calculating response checksum */
-	csum = msg->command + args.flags +
-		args.command_version + args.data_size;
+	sum = msg->command + args.flags + args.command_version + args.data_size;
 
 	/* Read response and update checksum */
-	for (i = 0; i < args.data_size; i++) {
-		msg->data[i] = inb(EC_LPC_ADDR_HOST_PARAM + i);
-		csum += msg->data[i];
-	}
+	sum += cros_ec_lpc_read_bytes(EC_LPC_ADDR_HOST_PARAM, args.data_size,
+				      msg->data);
 
 	/* Verify checksum */
-	if (args.checksum != (csum & 0xFF)) {
+	if (args.checksum != sum) {
 		dev_err(ec->dev,
 			"bad packet checksum, expected %02x, got %02x\n",
-			args.checksum, csum & 0xFF);
+			args.checksum, sum);
 		ret = -EBADMSG;
 		goto done;
 	}
@@ -222,14 +210,13 @@ static int cros_ec_lpc_readmem(struct cros_ec_device *ec, unsigned int offset,
 
 	/* fixed length */
 	if (bytes) {
-		for (; cnt < bytes; i++, s++, cnt++)
-			*s = inb(EC_LPC_ADDR_MEMMAP + i);
-		return cnt;
+		cros_ec_lpc_read_bytes(EC_LPC_ADDR_MEMMAP + offset, bytes, s);
+		return bytes;
 	}
 
 	/* string */
 	for (; i < EC_MEMMAP_SIZE; i++, s++) {
-		*s = inb(EC_LPC_ADDR_MEMMAP + i);
+		cros_ec_lpc_read_bytes(EC_LPC_ADDR_MEMMAP + i, 1, s);
 		cnt++;
 		if (!*s)
 			break;
@@ -242,6 +229,7 @@ static int cros_ec_lpc_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct cros_ec_device *ec_dev;
+	u8 buf[2];
 	int ret;
 
 	if (!devm_request_region(dev, EC_LPC_ADDR_MEMMAP, EC_MEMMAP_SIZE,
@@ -250,8 +238,8 @@ static int cros_ec_lpc_probe(struct platform_device *pdev)
 		return -EBUSY;
 	}
 
-	if ((inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID) != 'E') ||
-	    (inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID + 1) != 'C')) {
+	cros_ec_lpc_read_bytes(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID, 2, buf);
+	if (buf[0] != 'E' || buf[1] != 'C') {
 		dev_err(dev, "EC ID not detected\n");
 		return -ENODEV;
 	}
diff --git a/drivers/platform/chrome/cros_ec_lpc_reg.c b/drivers/platform/chrome/cros_ec_lpc_reg.c
new file mode 100644
index 0000000..03c9781
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lpc_reg.c
@@ -0,0 +1,64 @@
+/*
+ * cros_ec_lpc_reg - LPC access to the Chrome OS Embedded Controller
+ *
+ * Copyright (C) 2016 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ * This driver uses the Chrome OS EC byte-level message-based protocol for
+ * communicating the keyboard state (which keys are pressed) from a keyboard EC
+ * to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing,
+ * but everything else (including deghosting) is done here.  The main
+ * motivation for this is to keep the EC firmware as simple as possible, since
+ * it cannot be easily upgraded and EC flash/IRAM space is relatively
+ * expensive.
+ */
+
+#include <linux/io.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+
+static u8 lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
+{
+	int i;
+	int sum = 0;
+
+	for (i = 0; i < length; ++i) {
+		dest[i] = inb(offset + i);
+		sum += dest[i];
+	}
+
+	/* Return checksum of all bytes read */
+	return sum;
+}
+
+static u8 lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
+{
+	int i;
+	int sum = 0;
+
+	for (i = 0; i < length; ++i) {
+		outb(msg[i], offset + i);
+		sum += msg[i];
+	}
+
+	/* Return checksum of all bytes written */
+	return sum;
+}
+
+u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
+{
+	return lpc_read_bytes(offset, length, dest);
+}
+
+u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
+{
+	return lpc_write_bytes(offset, length, msg);
+}
diff --git a/include/linux/mfd/cros_ec_lpc_reg.h b/include/linux/mfd/cros_ec_lpc_reg.h
new file mode 100644
index 0000000..4089bd5
--- /dev/null
+++ b/include/linux/mfd/cros_ec_lpc_reg.h
@@ -0,0 +1,47 @@
+/*
+ * cros_ec_lpc_reg - LPC access to the Chrome OS Embedded Controller
+ *
+ * Copyright (C) 2016 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ * This driver uses the Chrome OS EC byte-level message-based protocol for
+ * communicating the keyboard state (which keys are pressed) from a keyboard EC
+ * to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing,
+ * but everything else (including deghosting) is done here.  The main
+ * motivation for this is to keep the EC firmware as simple as possible, since
+ * it cannot be easily upgraded and EC flash/IRAM space is relatively
+ * expensive.
+ */
+
+#ifndef __LINUX_MFD_CROS_EC_REG_H
+#define __LINUX_MFD_CROS_EC_REG_H
+
+/**
+ * cros_ec_lpc_read_bytes - Read bytes from a given LPC-mapped address.
+ * Returns 8-bit checksum of all bytes read.
+ *
+ * @offset: Base read address
+ * @length: Number of bytes to read
+ * @dest: Destination buffer
+ */
+u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest);
+
+/**
+ * cros_ec_lpc_write_bytes - Write bytes to a given LPC-mapped address.
+ * Returns 8-bit checksum of all bytes written.
+ *
+ * @offset: Base write address
+ * @length: Number of bytes to write
+ * @msg: Write data buffer
+ */
+u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg);
+
+#endif /* __LINUX_MFD_CROS_EC_REG_H */
-- 
2.7.4

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH v2 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC
  2016-12-02 15:35 [PATCH v2 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
  2016-12-02 15:35 ` [PATCH v2 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
@ 2016-12-02 15:35 ` Thierry Escande
  2016-12-02 15:39 ` [PATCH v2 0/2] platform/chrome: " Benson Leung
  2 siblings, 0 replies; 4+ messages in thread
From: Thierry Escande @ 2016-12-02 15:35 UTC (permalink / raw)
  To: Benson Leung; +Cc: linux-kernel

From: Shawn Nematbakhsh <shawnn@chromium.org>

This adds support for the ChromeOS LPC Microchip Embedded Controller
(mec1322) variant.

mec1322 accesses I/O region [800h, 9ffh] through embedded memory
interface (EMI) rather than LPC.

Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
---
 drivers/platform/chrome/Kconfig           |  12 +++
 drivers/platform/chrome/Makefile          |   1 +
 drivers/platform/chrome/cros_ec_lpc.c     |   5 ++
 drivers/platform/chrome/cros_ec_lpc_mec.c | 140 ++++++++++++++++++++++++++++++
 drivers/platform/chrome/cros_ec_lpc_reg.c |  69 +++++++++++++++
 include/linux/mfd/cros_ec_lpc_mec.h       |  90 +++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_reg.h       |  14 +++
 7 files changed, 331 insertions(+)
 create mode 100644 drivers/platform/chrome/cros_ec_lpc_mec.c
 create mode 100644 include/linux/mfd/cros_ec_lpc_mec.h

diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 76bdae1..6d80fb5 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -59,6 +59,18 @@ config CROS_EC_LPC
           To compile this driver as a module, choose M here: the
           module will be called cros_ec_lpc.
 
+config CROS_EC_LPC_MEC
+	bool "ChromeOS Embedded Controller LPC Microchip EC (MEC) variant"
+	depends on CROS_EC_LPC
+	default n
+	help
+	  If you say Y here, a variant LPC protocol for the Microchip EC
+	  will be used. Note that this variant is not backward compatible
+	  with non-Microchip ECs.
+
+	  If you have a ChromeOS Embedded Controller Microchip EC variant
+	  choose Y here.
+
 config CROS_EC_PROTO
         bool
         help
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 127fbe8..b8f7a3b 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -5,6 +5,7 @@ cros_ec_devs-objs			:= cros_ec_dev.o cros_ec_sysfs.o \
 					   cros_ec_lightbar.o cros_ec_vbc.o
 obj-$(CONFIG_CROS_EC_CHARDEV)		+= cros_ec_devs.o
 cros_ec_lpcs-objs			:= cros_ec_lpc.o cros_ec_lpc_reg.o
+cros_ec_lpcs-$(CONFIG_CROS_EC_LPC_MEC)	+= cros_ec_lpc_mec.o
 obj-$(CONFIG_CROS_EC_LPC)		+= cros_ec_lpcs.o
 obj-$(CONFIG_CROS_EC_PROTO)		+= cros_ec_proto.o
 obj-$(CONFIG_CROS_KBD_LED_BACKLIGHT)	+= cros_kbd_led_backlight.o
diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c
index 6a782a6..bc2dc62 100644
--- a/drivers/platform/chrome/cros_ec_lpc.c
+++ b/drivers/platform/chrome/cros_ec_lpc.c
@@ -346,10 +346,13 @@ static int __init cros_ec_lpc_init(void)
 		return -ENODEV;
 	}
 
+	cros_ec_lpc_reg_init();
+
 	/* Register the driver */
 	ret = platform_driver_register(&cros_ec_lpc_driver);
 	if (ret) {
 		pr_err(DRV_NAME ": can't register driver: %d\n", ret);
+		cros_ec_lpc_reg_destroy();
 		return ret;
 	}
 
@@ -358,6 +361,7 @@ static int __init cros_ec_lpc_init(void)
 	if (ret) {
 		pr_err(DRV_NAME ": can't register device: %d\n", ret);
 		platform_driver_unregister(&cros_ec_lpc_driver);
+		cros_ec_lpc_reg_destroy();
 		return ret;
 	}
 
@@ -368,6 +372,7 @@ static void __exit cros_ec_lpc_exit(void)
 {
 	platform_device_unregister(&cros_ec_lpc_device);
 	platform_driver_unregister(&cros_ec_lpc_driver);
+	cros_ec_lpc_reg_destroy();
 }
 
 module_init(cros_ec_lpc_init);
diff --git a/drivers/platform/chrome/cros_ec_lpc_mec.c b/drivers/platform/chrome/cros_ec_lpc_mec.c
new file mode 100644
index 0000000..2eda2c2
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lpc_mec.c
@@ -0,0 +1,140 @@
+/*
+ * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
+ *
+ * Copyright (C) 2016 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ * This driver uses the Chrome OS EC byte-level message-based protocol for
+ * communicating the keyboard state (which keys are pressed) from a keyboard EC
+ * to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing,
+ * but everything else (including deghosting) is done here.  The main
+ * motivation for this is to keep the EC firmware as simple as possible, since
+ * it cannot be easily upgraded and EC flash/IRAM space is relatively
+ * expensive.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/mfd/cros_ec_lpc_mec.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+/*
+ * This mutex must be held while accessing the EMI unit. We can't rely on the
+ * EC mutex because memmap data may be accessed without it being held.
+ */
+static struct mutex io_mutex;
+
+/*
+ * cros_ec_lpc_mec_emi_write_address
+ *
+ * Initialize EMI read / write at a given address.
+ *
+ * @addr:        Starting read / write address
+ * @access_type: Type of access, typically 32-bit auto-increment
+ */
+static void cros_ec_lpc_mec_emi_write_address(u16 addr,
+			enum cros_ec_lpc_mec_emi_access_mode access_type)
+{
+	/* Address relative to start of EMI range */
+	addr -= MEC_EMI_RANGE_START;
+	outb((addr & 0xfc) | access_type, MEC_EMI_EC_ADDRESS_B0);
+	outb((addr >> 8) & 0x7f, MEC_EMI_EC_ADDRESS_B1);
+}
+
+/*
+ * cros_ec_lpc_io_bytes_mec - Read / write bytes to MEC EMI port
+ *
+ * @io_type: MEC_IO_READ or MEC_IO_WRITE, depending on request
+ * @offset:  Base read / write address
+ * @length:  Number of bytes to read / write
+ * @buf:     Destination / source buffer
+ *
+ * @return 8-bit checksum of all bytes read / written
+ */
+u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
+			    unsigned int offset, unsigned int length,
+			    u8 *buf)
+{
+	int i = 0;
+	int io_addr;
+	u8 sum = 0;
+	enum cros_ec_lpc_mec_emi_access_mode access, new_access;
+
+	/*
+	 * Long access cannot be used on misaligned data since reading B0 loads
+	 * the data register and writing B3 flushes.
+	 */
+	if (offset & 0x3 || length < 4)
+		access = ACCESS_TYPE_BYTE;
+	else
+		access = ACCESS_TYPE_LONG_AUTO_INCREMENT;
+
+	mutex_lock(&io_mutex);
+
+	/* Initialize I/O at desired address */
+	cros_ec_lpc_mec_emi_write_address(offset, access);
+
+	/* Skip bytes in case of misaligned offset */
+	io_addr = MEC_EMI_EC_DATA_B0 + (offset & 0x3);
+	while (i < length) {
+		while (io_addr <= MEC_EMI_EC_DATA_B3) {
+			if (io_type == MEC_IO_READ)
+				buf[i] = inb(io_addr++);
+			else
+				outb(buf[i], io_addr++);
+
+			sum += buf[i++];
+			offset++;
+
+			/* Extra bounds check in case of misaligned length */
+			if (i == length)
+				goto done;
+		}
+
+		/*
+		 * Use long auto-increment access except for misaligned write,
+		 * since writing B3 triggers the flush.
+		 */
+		if (length - i < 4 && io_type == MEC_IO_WRITE)
+			new_access = ACCESS_TYPE_BYTE;
+		else
+			new_access = ACCESS_TYPE_LONG_AUTO_INCREMENT;
+
+		if (new_access != access ||
+		    access != ACCESS_TYPE_LONG_AUTO_INCREMENT) {
+			access = new_access;
+			cros_ec_lpc_mec_emi_write_address(offset, access);
+		}
+
+		/* Access [B0, B3] on each loop pass */
+		io_addr = MEC_EMI_EC_DATA_B0;
+	}
+
+done:
+	mutex_unlock(&io_mutex);
+
+	return sum;
+}
+EXPORT_SYMBOL(cros_ec_lpc_io_bytes_mec);
+
+void cros_ec_lpc_mec_init(void)
+{
+	mutex_init(&io_mutex);
+}
+EXPORT_SYMBOL(cros_ec_lpc_mec_init);
+
+void cros_ec_lpc_mec_destroy(void)
+{
+	mutex_destroy(&io_mutex);
+}
+EXPORT_SYMBOL(cros_ec_lpc_mec_destroy);
diff --git a/drivers/platform/chrome/cros_ec_lpc_reg.c b/drivers/platform/chrome/cros_ec_lpc_reg.c
index 03c9781..dcc7a3e 100644
--- a/drivers/platform/chrome/cros_ec_lpc_reg.c
+++ b/drivers/platform/chrome/cros_ec_lpc_reg.c
@@ -24,6 +24,7 @@
 #include <linux/io.h>
 #include <linux/mfd/cros_ec.h>
 #include <linux/mfd/cros_ec_commands.h>
+#include <linux/mfd/cros_ec_lpc_mec.h>
 
 static u8 lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
 {
@@ -53,12 +54,80 @@ static u8 lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
 	return sum;
 }
 
+#ifdef CONFIG_CROS_EC_LPC_MEC
+
 u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
 {
+	if (length == 0)
+		return 0;
+
+	/* Access desired range through EMI interface */
+	if (offset >= MEC_EMI_RANGE_START && offset <= MEC_EMI_RANGE_END) {
+		/* Ensure we don't straddle EMI region */
+		if (WARN_ON(offset + length - 1 > MEC_EMI_RANGE_END))
+			return 0;
+
+		return cros_ec_lpc_io_bytes_mec(MEC_IO_READ, offset, length,
+						dest);
+	}
+
+	if (WARN_ON(offset + length > MEC_EMI_RANGE_START &&
+		    offset < MEC_EMI_RANGE_START))
+		return 0;
+
 	return lpc_read_bytes(offset, length, dest);
 }
 
 u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
 {
+	if (length == 0)
+		return 0;
+
+	/* Access desired range through EMI interface */
+	if (offset >= MEC_EMI_RANGE_START && offset <= MEC_EMI_RANGE_END) {
+		/* Ensure we don't straddle EMI region */
+		if (WARN_ON(offset + length - 1 > MEC_EMI_RANGE_END))
+			return 0;
+
+		return cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, offset, length,
+						msg);
+	}
+
+	if (WARN_ON(offset + length > MEC_EMI_RANGE_START &&
+		    offset < MEC_EMI_RANGE_START))
+		return 0;
+
 	return lpc_write_bytes(offset, length, msg);
 }
+
+void cros_ec_lpc_reg_init(void)
+{
+	cros_ec_lpc_mec_init();
+}
+
+void cros_ec_lpc_reg_destroy(void)
+{
+	cros_ec_lpc_mec_destroy();
+}
+
+#else /* CONFIG_CROS_EC_LPC_MEC */
+
+u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest)
+{
+	return lpc_read_bytes(offset, length, dest);
+}
+
+u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg)
+{
+	return lpc_write_bytes(offset, length, msg);
+}
+
+void cros_ec_lpc_reg_init(void)
+{
+}
+
+void cros_ec_lpc_reg_destroy(void)
+{
+}
+
+#endif /* CONFIG_CROS_EC_LPC_MEC */
diff --git a/include/linux/mfd/cros_ec_lpc_mec.h b/include/linux/mfd/cros_ec_lpc_mec.h
new file mode 100644
index 0000000..176496d
--- /dev/null
+++ b/include/linux/mfd/cros_ec_lpc_mec.h
@@ -0,0 +1,90 @@
+/*
+ * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
+ *
+ * Copyright (C) 2016 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ * This driver uses the Chrome OS EC byte-level message-based protocol for
+ * communicating the keyboard state (which keys are pressed) from a keyboard EC
+ * to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing,
+ * but everything else (including deghosting) is done here.  The main
+ * motivation for this is to keep the EC firmware as simple as possible, since
+ * it cannot be easily upgraded and EC flash/IRAM space is relatively
+ * expensive.
+ */
+
+#ifndef __LINUX_MFD_CROS_EC_MEC_H
+#define __LINUX_MFD_CROS_EC_MEC_H
+
+#include <linux/mfd/cros_ec_commands.h>
+
+enum cros_ec_lpc_mec_emi_access_mode {
+	/* 8-bit access */
+	ACCESS_TYPE_BYTE = 0x0,
+	/* 16-bit access */
+	ACCESS_TYPE_WORD = 0x1,
+	/* 32-bit access */
+	ACCESS_TYPE_LONG = 0x2,
+	/*
+	 * 32-bit access, read or write of MEC_EMI_EC_DATA_B3 causes the
+	 * EC data register to be incremented.
+	 */
+	ACCESS_TYPE_LONG_AUTO_INCREMENT = 0x3,
+};
+
+enum cros_ec_lpc_mec_io_type {
+	MEC_IO_READ,
+	MEC_IO_WRITE,
+};
+
+/* Access IO ranges 0x800 thru 0x9ff using EMI interface instead of LPC */
+#define MEC_EMI_RANGE_START EC_HOST_CMD_REGION0
+#define MEC_EMI_RANGE_END   (EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE)
+
+/* EMI registers are relative to base */
+#define MEC_EMI_BASE 0x800
+#define MEC_EMI_HOST_TO_EC (MEC_EMI_BASE + 0)
+#define MEC_EMI_EC_TO_HOST (MEC_EMI_BASE + 1)
+#define MEC_EMI_EC_ADDRESS_B0 (MEC_EMI_BASE + 2)
+#define MEC_EMI_EC_ADDRESS_B1 (MEC_EMI_BASE + 3)
+#define MEC_EMI_EC_DATA_B0 (MEC_EMI_BASE + 4)
+#define MEC_EMI_EC_DATA_B1 (MEC_EMI_BASE + 5)
+#define MEC_EMI_EC_DATA_B2 (MEC_EMI_BASE + 6)
+#define MEC_EMI_EC_DATA_B3 (MEC_EMI_BASE + 7)
+
+/*
+ * cros_ec_lpc_mec_init
+ *
+ * Initialize MEC I/O.
+ */
+void cros_ec_lpc_mec_init(void);
+
+/*
+ * cros_ec_lpc_mec_destroy
+ *
+ * Cleanup MEC I/O.
+ */
+void cros_ec_lpc_mec_destroy(void);
+
+/**
+ * cros_ec_lpc_io_bytes_mec - Read / write bytes to MEC EMI port
+ *
+ * @io_type: MEC_IO_READ or MEC_IO_WRITE, depending on request
+ * @offset:  Base read / write address
+ * @length:  Number of bytes to read / write
+ * @buf:     Destination / source buffer
+ *
+ * @return 8-bit checksum of all bytes read / written
+ */
+u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
+			    unsigned int offset, unsigned int length, u8 *buf);
+
+#endif /* __LINUX_MFD_CROS_EC_MEC_H */
diff --git a/include/linux/mfd/cros_ec_lpc_reg.h b/include/linux/mfd/cros_ec_lpc_reg.h
index 4089bd5..5560bef 100644
--- a/include/linux/mfd/cros_ec_lpc_reg.h
+++ b/include/linux/mfd/cros_ec_lpc_reg.h
@@ -44,4 +44,18 @@ u8 cros_ec_lpc_read_bytes(unsigned int offset, unsigned int length, u8 *dest);
  */
 u8 cros_ec_lpc_write_bytes(unsigned int offset, unsigned int length, u8 *msg);
 
+/**
+ * cros_ec_lpc_reg_init
+ *
+ * Initialize register I/O.
+ */
+void cros_ec_lpc_reg_init(void);
+
+/**
+ * cros_ec_lpc_reg_destroy
+ *
+ * Cleanup reg I/O.
+ */
+void cros_ec_lpc_reg_destroy(void);
+
 #endif /* __LINUX_MFD_CROS_EC_REG_H */
-- 
2.7.4

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v2 0/2] platform/chrome: Add support for mec1322 EC
  2016-12-02 15:35 [PATCH v2 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
  2016-12-02 15:35 ` [PATCH v2 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
  2016-12-02 15:35 ` [PATCH v2 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
@ 2016-12-02 15:39 ` Benson Leung
  2 siblings, 0 replies; 4+ messages in thread
From: Benson Leung @ 2016-12-02 15:39 UTC (permalink / raw)
  To: Thierry Escande; +Cc: linux-kernel

Hi Thierry,

On Fri, Dec 2, 2016 at 7:35 AM, Thierry Escande
<thierry.escande@collabora.com> wrote:
> Hi Benson,
>
> This series adds support for the LPC Microchip Embedded Controller 1322.

Thanks. I'll queue these up for the first batch of changes I'll work
on as chrome platform maintainer.

>
> v2:
> -Add a few lines in Kconfig description
> -Fixed coding style issues
> -Updated copyright to year 2016
>
> Shawn Nematbakhsh (2):
>   platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants
>   platform/chrome: cros_ec_lpc: Add support for mec1322 EC
>
>  drivers/platform/chrome/Kconfig           |  12 +++
>  drivers/platform/chrome/Makefile          |   4 +-
>  drivers/platform/chrome/cros_ec_lpc.c     |  93 +++++++++-----------
>  drivers/platform/chrome/cros_ec_lpc_mec.c | 140 ++++++++++++++++++++++++++++++
>  drivers/platform/chrome/cros_ec_lpc_reg.c | 133 ++++++++++++++++++++++++++++
>  include/linux/mfd/cros_ec_lpc_mec.h       |  90 +++++++++++++++++++
>  include/linux/mfd/cros_ec_lpc_reg.h       |  61 +++++++++++++
>  7 files changed, 482 insertions(+), 51 deletions(-)
>  create mode 100644 drivers/platform/chrome/cros_ec_lpc_mec.c
>  create mode 100644 drivers/platform/chrome/cros_ec_lpc_reg.c
>  create mode 100644 include/linux/mfd/cros_ec_lpc_mec.h
>  create mode 100644 include/linux/mfd/cros_ec_lpc_reg.h
>
> --
> 2.7.4
>



-- 
Benson Leung
Senior Software Engineer
Chrome OS Kernel
Google Inc.
bleung@google.com
Chromium OS Project
bleung@chromium.org

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2016-12-02 15:40 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-12-02 15:35 [PATCH v2 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
2016-12-02 15:35 ` [PATCH v2 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
2016-12-02 15:35 ` [PATCH v2 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
2016-12-02 15:39 ` [PATCH v2 0/2] platform/chrome: " Benson Leung

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