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* [PATCH RESEND 0/2] platform/chrome: Add support for mec1322 EC
@ 2016-11-08 12:27 Thierry Escande
  2016-11-08 12:27 ` [PATCH RESEND 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
  2016-11-08 12:27 ` [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
  0 siblings, 2 replies; 5+ messages in thread
From: Thierry Escande @ 2016-11-08 12:27 UTC (permalink / raw)
  To: bleung; +Cc: linux-kernel

Hi,

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

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           |   9 ++
 drivers/platform/chrome/Makefile          |   4 +-
 drivers/platform/chrome/cros_ec_lpc.c     |  92 +++++++++----------
 drivers/platform/chrome/cros_ec_lpc_mec.c | 144 ++++++++++++++++++++++++++++++
 drivers/platform/chrome/cros_ec_lpc_reg.c | 133 +++++++++++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_mec.h       |  93 +++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_reg.h       |  61 +++++++++++++
 7 files changed, 487 insertions(+), 49 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] 5+ messages in thread

* [PATCH RESEND 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants
  2016-11-08 12:27 [PATCH RESEND 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
@ 2016-11-08 12:27 ` Thierry Escande
  2016-11-08 12:27 ` [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
  1 sibling, 0 replies; 5+ messages in thread
From: Thierry Escande @ 2016-11-08 12:27 UTC (permalink / raw)
  To: bleung; +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: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
---
 drivers/platform/chrome/Makefile          |  3 +-
 drivers/platform/chrome/cros_ec_lpc.c     | 87 ++++++++++++++-----------------
 drivers/platform/chrome/cros_ec_lpc_reg.c | 64 +++++++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_reg.h       | 47 +++++++++++++++++
 4 files changed, 152 insertions(+), 49 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..617074e 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 +97,10 @@ 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 +120,7 @@ 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 +137,21 @@ static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
 	args.data_size = msg->outsize;
 
 	/* Initialize checksum */
-	csum = msg->command + args.flags +
+	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 +160,14 @@ 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 +178,18 @@ static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
 	}
 
 	/* Start calculating response checksum */
-	csum = msg->command + args.flags +
+	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 +213,13 @@ 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 +232,7 @@ 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 +241,8 @@ 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..672d08c
--- /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) 2015 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..f3668ab
--- /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) 2015 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 related	[flat|nested] 5+ messages in thread

* [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC
  2016-11-08 12:27 [PATCH RESEND 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
  2016-11-08 12:27 ` [PATCH RESEND 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
@ 2016-11-08 12:27 ` Thierry Escande
  2016-11-30 15:48   ` Enric Balletbo Serra
  1 sibling, 1 reply; 5+ messages in thread
From: Thierry Escande @ 2016-11-08 12:27 UTC (permalink / raw)
  To: bleung; +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: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
---
 drivers/platform/chrome/Kconfig           |   9 ++
 drivers/platform/chrome/Makefile          |   1 +
 drivers/platform/chrome/cros_ec_lpc.c     |   5 ++
 drivers/platform/chrome/cros_ec_lpc_mec.c | 144 ++++++++++++++++++++++++++++++
 drivers/platform/chrome/cros_ec_lpc_reg.c |  69 ++++++++++++++
 include/linux/mfd/cros_ec_lpc_mec.h       |  93 +++++++++++++++++++
 include/linux/mfd/cros_ec_lpc_reg.h       |  14 +++
 7 files changed, 335 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..55149f2 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -59,6 +59,15 @@ 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.
+
 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 617074e..264234b 100644
--- a/drivers/platform/chrome/cros_ec_lpc.c
+++ b/drivers/platform/chrome/cros_ec_lpc.c
@@ -349,10 +349,13 @@ 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;
 	}
 
@@ -361,6 +364,7 @@ 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;
 	}
 
@@ -371,6 +375,7 @@ 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..09e2e21
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lpc_mec.c
@@ -0,0 +1,144 @@
+/*
+ * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
+ *
+ * Copyright (C) 2015 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(
+	uint16_t 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 672d08c..afb29c4 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..69da593
--- /dev/null
+++ b/include/linux/mfd/cros_ec_lpc_mec.h
@@ -0,0 +1,93 @@
+/*
+ * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
+ *
+ * Copyright (C) 2015 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 f3668ab..daede3a 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 related	[flat|nested] 5+ messages in thread

* Re: [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC
  2016-11-08 12:27 ` [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
@ 2016-11-30 15:48   ` Enric Balletbo Serra
  2016-12-01 16:55     ` Thierry Escande
  0 siblings, 1 reply; 5+ messages in thread
From: Enric Balletbo Serra @ 2016-11-30 15:48 UTC (permalink / raw)
  To: Thierry Escande; +Cc: Benson Leung, linux-kernel

Hi Thierry,

I reviewed your patches and looks good to me, I only found a few style
things that is up to maintainer decide if are needed or not, most of
them are feedback I received on other subsystems. Ah, and I've a
question about runtime detection of the EC (see below), but guess the
answer is no.

Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

2016-11-08 13:27 GMT+01:00 Thierry Escande <thierry.escande@collabora.com>:
> 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: Gwendal Grignou <gwendal@chromium.org>
> Signed-off-by: Guenter Roeck <groeck@chromium.org>
> Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
> ---
>  drivers/platform/chrome/Kconfig           |   9 ++
>  drivers/platform/chrome/Makefile          |   1 +
>  drivers/platform/chrome/cros_ec_lpc.c     |   5 ++
>  drivers/platform/chrome/cros_ec_lpc_mec.c | 144 ++++++++++++++++++++++++++++++
>  drivers/platform/chrome/cros_ec_lpc_reg.c |  69 ++++++++++++++
>  include/linux/mfd/cros_ec_lpc_mec.h       |  93 +++++++++++++++++++
>  include/linux/mfd/cros_ec_lpc_reg.h       |  14 +++
>  7 files changed, 335 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..55149f2 100644
> --- a/drivers/platform/chrome/Kconfig
> +++ b/drivers/platform/chrome/Kconfig
> @@ -59,6 +59,15 @@ 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.
> +

As reported by checkpatch, write a paragraph that describes the config
symbol fully. Maybe adding something like this

          If you have a ChromeOS Embedded Controller Microchip EC variant
          choose Y here.

According to the help if you have a non-Microchip EC you should leave
this as N. Would be possible some kind of runtime detection of the EC
? Just thinking in out loud.

>  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 617074e..264234b 100644
> --- a/drivers/platform/chrome/cros_ec_lpc.c
> +++ b/drivers/platform/chrome/cros_ec_lpc.c
> @@ -349,10 +349,13 @@ 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;
>         }
>
> @@ -361,6 +364,7 @@ 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;
>         }
>
> @@ -371,6 +375,7 @@ 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..09e2e21
> --- /dev/null
> +++ b/drivers/platform/chrome/cros_ec_lpc_mec.c
> @@ -0,0 +1,144 @@
> +/*
> + * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
> + *
> + * Copyright (C) 2015 Google, Inc
> + *

Update the copyright to 2016

> + * 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(
> +       uint16_t addr,

It is preferred use type u16 over uint16_t

> +       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)

nit: When possible alignment should match open parenthesis. I'd define
the function as:

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);
> +

This fits in one line.

> +       /* 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);

This also fits in one line.

> +               }
> +
> +               /* Access [B0, B3] on each loop pass */
> +               io_addr = MEC_EMI_EC_DATA_B0;
> +       }
> +done:
> +       mutex_unlock(&io_mutex);

Add an empty line here

> +       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 672d08c..afb29c4 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..69da593
> --- /dev/null
> +++ b/include/linux/mfd/cros_ec_lpc_mec.h
> @@ -0,0 +1,93 @@
> +/*
> + * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
> + *
> + * Copyright (C) 2015 Google, Inc
> + *

Update the copyright.

> + * 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 f3668ab..daede3a 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] 5+ messages in thread

* Re: [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC
  2016-11-30 15:48   ` Enric Balletbo Serra
@ 2016-12-01 16:55     ` Thierry Escande
  0 siblings, 0 replies; 5+ messages in thread
From: Thierry Escande @ 2016-12-01 16:55 UTC (permalink / raw)
  To: Enric Balletbo Serra; +Cc: Benson Leung, linux-kernel

Hi Enric,

Thanks for the review.

On 30/11/2016 16:48, Enric Balletbo Serra wrote:
> Hi Thierry,
>
> I reviewed your patches and looks good to me, I only found a few style
> things that is up to maintainer decide if are needed or not, most of
> them are feedback I received on other subsystems. Ah, and I've a
> question about runtime detection of the EC (see below), but guess the
> answer is no.
>
> Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
>
> 2016-11-08 13:27 GMT+01:00 Thierry Escande <thierry.escande@collabora.com>:
>> 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: Gwendal Grignou <gwendal@chromium.org>
>> Signed-off-by: Guenter Roeck <groeck@chromium.org>
>> Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
>> ---
>>  drivers/platform/chrome/Kconfig           |   9 ++
>>  drivers/platform/chrome/Makefile          |   1 +
>>  drivers/platform/chrome/cros_ec_lpc.c     |   5 ++
>>  drivers/platform/chrome/cros_ec_lpc_mec.c | 144 ++++++++++++++++++++++++++++++
>>  drivers/platform/chrome/cros_ec_lpc_reg.c |  69 ++++++++++++++
>>  include/linux/mfd/cros_ec_lpc_mec.h       |  93 +++++++++++++++++++
>>  include/linux/mfd/cros_ec_lpc_reg.h       |  14 +++
>>  7 files changed, 335 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..55149f2 100644
>> --- a/drivers/platform/chrome/Kconfig
>> +++ b/drivers/platform/chrome/Kconfig
>> @@ -59,6 +59,15 @@ 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.
>> +
>
> As reported by checkpatch, write a paragraph that describes the config
> symbol fully. Maybe adding something like this
>
>           If you have a ChromeOS Embedded Controller Microchip EC variant
>           choose Y here.
>
> According to the help if you have a non-Microchip EC you should leave
> this as N. Would be possible some kind of runtime detection of the EC
> ? Just thinking in out loud.
Well, we can use the EC_CMD_GET_CHIP_INFO command and check for the chip 
name as it is "mec1322" (at least on the cyan that I have).

Regards,
  Thierry

>
>>  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 617074e..264234b 100644
>> --- a/drivers/platform/chrome/cros_ec_lpc.c
>> +++ b/drivers/platform/chrome/cros_ec_lpc.c
>> @@ -349,10 +349,13 @@ 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;
>>         }
>>
>> @@ -361,6 +364,7 @@ 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;
>>         }
>>
>> @@ -371,6 +375,7 @@ 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..09e2e21
>> --- /dev/null
>> +++ b/drivers/platform/chrome/cros_ec_lpc_mec.c
>> @@ -0,0 +1,144 @@
>> +/*
>> + * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
>> + *
>> + * Copyright (C) 2015 Google, Inc
>> + *
>
> Update the copyright to 2016
>
>> + * 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(
>> +       uint16_t addr,
>
> It is preferred use type u16 over uint16_t
>
>> +       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)
>
> nit: When possible alignment should match open parenthesis. I'd define
> the function as:
>
> 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);
>> +
>
> This fits in one line.
>
>> +       /* 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);
>
> This also fits in one line.
>
>> +               }
>> +
>> +               /* Access [B0, B3] on each loop pass */
>> +               io_addr = MEC_EMI_EC_DATA_B0;
>> +       }
>> +done:
>> +       mutex_unlock(&io_mutex);
>
> Add an empty line here
>
>> +       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 672d08c..afb29c4 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..69da593
>> --- /dev/null
>> +++ b/include/linux/mfd/cros_ec_lpc_mec.h
>> @@ -0,0 +1,93 @@
>> +/*
>> + * cros_ec_lpc_mec - LPC variant I/O for Microchip EC
>> + *
>> + * Copyright (C) 2015 Google, Inc
>> + *
>
> Update the copyright.
>
>> + * 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 f3668ab..daede3a 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] 5+ messages in thread

end of thread, other threads:[~2016-12-01 16:56 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-11-08 12:27 [PATCH RESEND 0/2] platform/chrome: Add support for mec1322 EC Thierry Escande
2016-11-08 12:27 ` [PATCH RESEND 1/2] platform/chrome: cros_ec_lpc: Add R/W helpers to LPC protocol variants Thierry Escande
2016-11-08 12:27 ` [PATCH RESEND 2/2] platform/chrome: cros_ec_lpc: Add support for mec1322 EC Thierry Escande
2016-11-30 15:48   ` Enric Balletbo Serra
2016-12-01 16:55     ` Thierry Escande

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