Merge tag 'chrome-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform

Pull chrome platform updates from Olof Johansson:
 "Here's a set of updates to the Chrome OS platform drivers for this
  merge window.

  Main new things this cycle is:

   - Driver changes to expose the lightbar to users.  With this, you can
     make your own blinkenlights on Chromebook Pixels.

   - Changes in the way that the atmel_mxt trackpads are probed.  The
     laptop driver is trying to be smart and not instantiate the devices
     that don't answer to probe.  For the trackpad that can come up in
     two modes (bootloader or regular), this gets complicated since the
     driver already knows how to handle the two modes including the
     actual addresses used.  So now the laptop driver needs to know more
     too, instantiating the regular address even if the bootloader one
     is the probe that passed.

   - mfd driver improvements by Javier Martines Canillas, and a few
     bugfixes from him, kbuild and myself"

* tag 'chrome-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform:
  platform/chrome: chromeos_laptop - instantiate Atmel at primary address
  platform/chrome: cros_ec_lpc - Depend on X86 || COMPILE_TEST
  platform/chrome: cros_ec_lpc - Include linux/io.h header file
  platform/chrome: fix platform_no_drv_owner.cocci warnings
  platform/chrome: cros_ec_lightbar - fix duplicate const warning
  platform/chrome: cros_ec_dev - fix Unknown escape '%' warning
  platform/chrome: Expose Chrome OS Lightbar to users
  platform/chrome: Create sysfs attributes for the ChromeOS EC
  mfd: cros_ec: Instantiate ChromeOS EC character device
  platform/chrome: Add Chrome OS EC userspace device interface
  platform/chrome: Add cros_ec_lpc driver for x86 devices
  mfd: cros_ec: Add char dev and virtual dev pointers
  mfd: cros_ec: Use fixed size arrays to transfer data with the EC

1 files changed, 319 insertions, 0 deletions

diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c
new file mode 100644
index 000000000000..8f9ac4d7bbd0
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lpc.c
@@ -0,0 +1,319 @@
+/*
+ * cros_ec_lpc - LPC access to the Chrome OS Embedded Controller
+ *
+ * Copyright (C) 2012-2015 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/dmi.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+
+#define DRV_NAME "cros_ec_lpc"
+
+static int ec_response_timed_out(void)
+{
+	unsigned long one_second = jiffies + HZ;
+
+	usleep_range(200, 300);
+	do {
+		if (!(inb(EC_LPC_ADDR_HOST_CMD) & EC_LPC_STATUS_BUSY_MASK))
+			return 0;
+		usleep_range(100, 200);
+	} while (time_before(jiffies, one_second));
+
+	return 1;
+}
+
+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;
+	int ret = 0;
+
+	if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE ||
+	    msg->insize > EC_PROTO2_MAX_PARAM_SIZE) {
+		dev_err(ec->dev,
+			"invalid buffer sizes (out %d, in %d)\n",
+			msg->outsize, msg->insize);
+		return -EINVAL;
+	}
+
+	/* Now actually send the command to the EC and get the result */
+	args.flags = EC_HOST_ARGS_FLAG_FROM_HOST;
+	args.command_version = msg->version;
+	args.data_size = msg->outsize;
+
+	/* Initialize checksum */
+	csum = msg->command + args.flags +
+		args.command_version + args.data_size;
+
+	/* Copy data and update checksum */
+	for (i = 0; i < msg->outsize; i++) {
+		outb(msg->outdata[i], EC_LPC_ADDR_HOST_PARAM + i);
+		csum += msg->outdata[i];
+	}
+
+	/* 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);
+
+	/* Here we go */
+	outb(msg->command, EC_LPC_ADDR_HOST_CMD);
+
+	if (ec_response_timed_out()) {
+		dev_warn(ec->dev, "EC responsed timed out\n");
+		ret = -EIO;
+		goto done;
+	}
+
+	/* Check result */
+	msg->result = inb(EC_LPC_ADDR_HOST_DATA);
+
+	switch (msg->result) {
+	case EC_RES_SUCCESS:
+		break;
+	case EC_RES_IN_PROGRESS:
+		ret = -EAGAIN;
+		dev_dbg(ec->dev, "command 0x%02x in progress\n",
+			msg->command);
+		goto done;
+	default:
+		dev_dbg(ec->dev, "command 0x%02x returned %d\n",
+			msg->command, msg->result);
+	}
+
+	/* 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);
+
+	if (args.data_size > msg->insize) {
+		dev_err(ec->dev,
+			"packet too long (%d bytes, expected %d)",
+			args.data_size, msg->insize);
+		ret = -ENOSPC;
+		goto done;
+	}
+
+	/* Start calculating response checksum */
+	csum = msg->command + args.flags +
+		args.command_version + args.data_size;
+
+	/* Read response and update checksum */
+	for (i = 0; i < args.data_size; i++) {
+		msg->indata[i] = inb(EC_LPC_ADDR_HOST_PARAM + i);
+		csum += msg->indata[i];
+	}
+
+	/* Verify checksum */
+	if (args.checksum != (csum & 0xFF)) {
+		dev_err(ec->dev,
+			"bad packet checksum, expected %02x, got %02x\n",
+			args.checksum, csum & 0xFF);
+		ret = -EBADMSG;
+		goto done;
+	}
+
+	/* Return actual amount of data received */
+	ret = args.data_size;
+done:
+	return ret;
+}
+
+/* Returns num bytes read, or negative on error. Doesn't need locking. */
+static int cros_ec_lpc_readmem(struct cros_ec_device *ec, unsigned int offset,
+			       unsigned int bytes, void *dest)
+{
+	int i = offset;
+	char *s = dest;
+	int cnt = 0;
+
+	if (offset >= EC_MEMMAP_SIZE - bytes)
+		return -EINVAL;
+
+	/* fixed length */
+	if (bytes) {
+		for (; cnt < bytes; i++, s++, cnt++)
+			*s = inb(EC_LPC_ADDR_MEMMAP + i);
+		return cnt;
+	}
+
+	/* string */
+	for (; i < EC_MEMMAP_SIZE; i++, s++) {
+		*s = inb(EC_LPC_ADDR_MEMMAP + i);
+		cnt++;
+		if (!*s)
+			break;
+	}
+
+	return cnt;
+}
+
+static int cros_ec_lpc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cros_ec_device *ec_dev;
+	int ret;
+
+	if (!devm_request_region(dev, EC_LPC_ADDR_MEMMAP, EC_MEMMAP_SIZE,
+				 dev_name(dev))) {
+		dev_err(dev, "couldn't reserve memmap region\n");
+		return -EBUSY;
+	}
+
+	if ((inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID) != 'E') ||
+	    (inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID + 1) != 'C')) {
+		dev_err(dev, "EC ID not detected\n");
+		return -ENODEV;
+	}
+
+	if (!devm_request_region(dev, EC_HOST_CMD_REGION0,
+				 EC_HOST_CMD_REGION_SIZE, dev_name(dev))) {
+		dev_err(dev, "couldn't reserve region0\n");
+		return -EBUSY;
+	}
+	if (!devm_request_region(dev, EC_HOST_CMD_REGION1,
+				 EC_HOST_CMD_REGION_SIZE, dev_name(dev))) {
+		dev_err(dev, "couldn't reserve region1\n");
+		return -EBUSY;
+	}
+
+	ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
+	if (!ec_dev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ec_dev);
+	ec_dev->dev = dev;
+	ec_dev->ec_name = pdev->name;
+	ec_dev->phys_name = dev_name(dev);
+	ec_dev->parent = dev;
+	ec_dev->cmd_xfer = cros_ec_cmd_xfer_lpc;
+	ec_dev->cmd_readmem = cros_ec_lpc_readmem;
+
+	ret = cros_ec_register(ec_dev);
+	if (ret) {
+		dev_err(dev, "couldn't register ec_dev (%d)\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int cros_ec_lpc_remove(struct platform_device *pdev)
+{
+	struct cros_ec_device *ec_dev;
+
+	ec_dev = platform_get_drvdata(pdev);
+	cros_ec_remove(ec_dev);
+
+	return 0;
+}
+
+static struct dmi_system_id cros_ec_lpc_dmi_table[] __initdata = {
+	{
+		/*
+		 * Today all Chromebooks/boxes ship with Google_* as version and
+		 * coreboot as bios vendor. No other systems with this
+		 * combination are known to date.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
+			DMI_MATCH(DMI_BIOS_VERSION, "Google_"),
+		},
+	},
+	{
+		/* x86-link, the Chromebook Pixel. */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Link"),
+		},
+	},
+	{
+		/* x86-peppy, the Acer C720 Chromebook. */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Peppy"),
+		},
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(dmi, cros_ec_lpc_dmi_table);
+
+static struct platform_driver cros_ec_lpc_driver = {
+	.driver = {
+		.name = DRV_NAME,
+	},
+	.probe = cros_ec_lpc_probe,
+	.remove = cros_ec_lpc_remove,
+};
+
+static struct platform_device cros_ec_lpc_device = {
+	.name = DRV_NAME
+};
+
+static int __init cros_ec_lpc_init(void)
+{
+	int ret;
+
+	if (!dmi_check_system(cros_ec_lpc_dmi_table)) {
+		pr_err(DRV_NAME ": unsupported system.\n");
+		return -ENODEV;
+	}
+
+	/* Register the driver */
+	ret = platform_driver_register(&cros_ec_lpc_driver);
+	if (ret) {
+		pr_err(DRV_NAME ": can't register driver: %d\n", ret);
+		return ret;
+	}
+
+	/* Register the device, and it'll get hooked up automatically */
+	ret = platform_device_register(&cros_ec_lpc_device);
+	if (ret) {
+		pr_err(DRV_NAME ": can't register device: %d\n", ret);
+		platform_driver_unregister(&cros_ec_lpc_driver);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void __exit cros_ec_lpc_exit(void)
+{
+	platform_device_unregister(&cros_ec_lpc_device);
+	platform_driver_unregister(&cros_ec_lpc_driver);
+}
+
+module_init(cros_ec_lpc_init);
+module_exit(cros_ec_lpc_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ChromeOS EC LPC driver");