[PATCH v7 00/10] Add support for OLPC XO 1.75 Embedded Controller

[PATCH v7 00/10] Add support for OLPC XO 1.75 Embedded Controller

[Lubomir Rintel]

Hello! 
 
This is a seventh spin of the patch set that adds support for the Embedded 
Controller on an OLPC XO 1.75 machine. 

The only patch that changed since v6 is [06/10]: there are fixes for
problems reported by Julia Lawall and the kbuild test robot.

The patch set depends on changes to the OLPC battery driver that have 
landed in the power-supply tree. Sebastian Reichel provided an signed
tag of an immutable branch that has the necessary bits and was merged
into the power-supply tree for 5.2: 
 
  git pull git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply.git psy-olpc-1.75-battery-signed 

The patch [10/10] was split of from the rest because Russell King found the 
patch [09/10] it depends on possibly objectionable. They should not be 
applied without further input from Russell.

Thank you, 
Lubo 

[PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Lubomir Rintel]

The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
signals for handshaking. It needs to know when is the slave (Linux)
side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
controller node) and when does it wish to respond with a command (the
cmd-gpio property).

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Rob Herring <robh@kernel.org>

---
Changes since v5:
- Added Rob Herring's Reviewed-by tag

Changes since v1:
- s/cmd-gpio/cmd-gpios/
- s/ready-gpio/ready-gpios/ in the documentation paragraph
- Remove status = "okay" from the example

 .../bindings/misc/olpc,xo1.75-ec.txt          | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt

diff --git a/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
new file mode 100644
index 000000000000..8c4d649cdd8f
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt
@@ -0,0 +1,23 @@
+OLPC XO-1.75 Embedded Controller
+
+Required properties:
+- compatible: Should be "olpc,xo1.75-ec".
+- cmd-gpios: gpio specifier of the CMD pin
+
+The embedded controller requires the SPI controller driver to signal readiness
+to receive a transfer (that is, when TX FIFO contains the response data) by
+strobing the ACK pin with the ready signal. See the "ready-gpios" property of the
+SSP binding as documented in:
+<Documentation/devicetree/bindings/spi/spi-pxa2xx.txt>.
+
+Example:
+	&ssp3 {
+		spi-slave;
+		ready-gpios = <&gpio 125 GPIO_ACTIVE_HIGH>;
+
+		slave {
+			compatible = "olpc,xo1.75-ec";
+			spi-cpha;
+			cmd-gpios = <&gpio 155 GPIO_ACTIVE_HIGH>;
+		};
+	};
-- 
2.21.0

[PATCH v7 02/10] Platform: OLPC: Remove an unused include

[Lubomir Rintel]

Also, the header is x86 specific, while there are non-x86 OLPC machines.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
---
 drivers/platform/olpc/olpc-ec.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/platform/olpc/olpc-ec.c b/drivers/platform/olpc/olpc-ec.c
index 374a8028fec7..981955dce926 100644
--- a/drivers/platform/olpc/olpc-ec.c
+++ b/drivers/platform/olpc/olpc-ec.c
@@ -17,7 +17,6 @@
 #include <linux/init.h>
 #include <linux/list.h>
 #include <linux/olpc-ec.h>
-#include <asm/olpc.h>
 
 struct ec_cmd_desc {
 	u8 cmd;
-- 
2.21.0

[PATCH v7 03/10] Platform: OLPC: Move EC-specific functionality out from x86

[Lubomir Rintel]

Move the olpc-ec driver away from the X86 OLPC platform so that it could be
used by the ARM based laptops too. Notably, the driver for the OLPC battery,
which is also used on the ARM models, builds on this driver's interface.

It is actually plaform independent: the OLPC EC commands with their argument
and responses are mostly the same despite the delivery mechanism is
different.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>

---
Changes since v4:
- A whitespace fix
- s/unisgned char ec_byte/u8 ec_byte/

Changes since v1:
- Cosmetic changes in line wrapping.
- Remove an old extra copy of EC_SCI_* defines
- Change version to u8
- Explain which parts are platform independent are in the commit message

 arch/x86/include/asm/olpc.h         |  31 --------
 arch/x86/platform/olpc/olpc.c       | 119 +++++-----------------------
 drivers/platform/olpc/olpc-ec.c     |  99 ++++++++++++++++++++++-
 drivers/power/supply/olpc_battery.c |   1 -
 include/linux/olpc-ec.h             |  32 +++++++-
 5 files changed, 145 insertions(+), 137 deletions(-)

diff --git a/arch/x86/include/asm/olpc.h b/arch/x86/include/asm/olpc.h
index c2bf1de5d901..6fe76282aceb 100644
--- a/arch/x86/include/asm/olpc.h
+++ b/arch/x86/include/asm/olpc.h
@@ -9,12 +9,10 @@
 struct olpc_platform_t {
 	int flags;
 	uint32_t boardrev;
-	int ecver;
 };
 
 #define OLPC_F_PRESENT		0x01
 #define OLPC_F_DCON		0x02
-#define OLPC_F_EC_WIDE_SCI	0x04
 
 #ifdef CONFIG_OLPC
 
@@ -64,13 +62,6 @@ static inline int olpc_board_at_least(uint32_t rev)
 	return olpc_platform_info.boardrev >= rev;
 }
 
-extern void olpc_ec_wakeup_set(u16 value);
-extern void olpc_ec_wakeup_clear(u16 value);
-extern bool olpc_ec_wakeup_available(void);
-
-extern int olpc_ec_mask_write(u16 bits);
-extern int olpc_ec_sci_query(u16 *sci_value);
-
 #else
 
 static inline int machine_is_olpc(void)
@@ -83,14 +74,6 @@ static inline int olpc_has_dcon(void)
 	return 0;
 }
 
-static inline void olpc_ec_wakeup_set(u16 value) { }
-static inline void olpc_ec_wakeup_clear(u16 value) { }
-
-static inline bool olpc_ec_wakeup_available(void)
-{
-	return false;
-}
-
 #endif
 
 #ifdef CONFIG_OLPC_XO1_PM
@@ -101,20 +84,6 @@ extern void olpc_xo1_pm_wakeup_clear(u16 value);
 
 extern int pci_olpc_init(void);
 
-/* SCI source values */
-
-#define EC_SCI_SRC_EMPTY	0x00
-#define EC_SCI_SRC_GAME		0x01
-#define EC_SCI_SRC_BATTERY	0x02
-#define EC_SCI_SRC_BATSOC	0x04
-#define EC_SCI_SRC_BATERR	0x08
-#define EC_SCI_SRC_EBOOK	0x10	/* XO-1 only */
-#define EC_SCI_SRC_WLAN		0x20	/* XO-1 only */
-#define EC_SCI_SRC_ACPWR	0x40
-#define EC_SCI_SRC_BATCRIT	0x80
-#define EC_SCI_SRC_GPWAKE	0x100	/* XO-1.5 only */
-#define EC_SCI_SRC_ALL		0x1FF
-
 /* GPIO assignments */
 
 #define OLPC_GPIO_MIC_AC	1
diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
index f0e920fb98ad..c6c62b4f251f 100644
--- a/arch/x86/platform/olpc/olpc.c
+++ b/arch/x86/platform/olpc/olpc.c
@@ -30,9 +30,6 @@
 struct olpc_platform_t olpc_platform_info;
 EXPORT_SYMBOL_GPL(olpc_platform_info);
 
-/* EC event mask to be applied during suspend (defining wakeup sources). */
-static u16 ec_wakeup_mask;
-
 /* what the timeout *should* be (in ms) */
 #define EC_BASE_TIMEOUT 20
 
@@ -186,83 +183,6 @@ static int olpc_xo1_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf,
 	return ret;
 }
 
-void olpc_ec_wakeup_set(u16 value)
-{
-	ec_wakeup_mask |= value;
-}
-EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set);
-
-void olpc_ec_wakeup_clear(u16 value)
-{
-	ec_wakeup_mask &= ~value;
-}
-EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear);
-
-/*
- * Returns true if the compile and runtime configurations allow for EC events
- * to wake the system.
- */
-bool olpc_ec_wakeup_available(void)
-{
-	if (!machine_is_olpc())
-		return false;
-
-	/*
-	 * XO-1 EC wakeups are available when olpc-xo1-sci driver is
-	 * compiled in
-	 */
-#ifdef CONFIG_OLPC_XO1_SCI
-	if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */
-		return true;
-#endif
-
-	/*
-	 * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
-	 * compiled in
-	 */
-#ifdef CONFIG_OLPC_XO15_SCI
-	if (olpc_platform_info.boardrev >= olpc_board_pre(0xd0)) /* XO-1.5 */
-		return true;
-#endif
-
-	return false;
-}
-EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);
-
-int olpc_ec_mask_write(u16 bits)
-{
-	if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
-		__be16 ec_word = cpu_to_be16(bits);
-		return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *) &ec_word, 2,
-				   NULL, 0);
-	} else {
-		unsigned char ec_byte = bits & 0xff;
-		return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0);
-	}
-}
-EXPORT_SYMBOL_GPL(olpc_ec_mask_write);
-
-int olpc_ec_sci_query(u16 *sci_value)
-{
-	int ret;
-
-	if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
-		__be16 ec_word;
-		ret = olpc_ec_cmd(EC_EXT_SCI_QUERY,
-			NULL, 0, (void *) &ec_word, 2);
-		if (ret == 0)
-			*sci_value = be16_to_cpu(ec_word);
-	} else {
-		unsigned char ec_byte;
-		ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1);
-		if (ret == 0)
-			*sci_value = ec_byte;
-	}
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(olpc_ec_sci_query);
-
 static bool __init check_ofw_architecture(struct device_node *root)
 {
 	const char *olpc_arch;
@@ -296,6 +216,10 @@ static bool __init platform_detect(void)
 	if (success) {
 		olpc_platform_info.boardrev = get_board_revision(root);
 		olpc_platform_info.flags |= OLPC_F_PRESENT;
+
+		pr_info("OLPC board revision %s%X\n",
+			((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
+			olpc_platform_info.boardrev >> 4);
 	}
 
 	of_node_put(root);
@@ -315,27 +239,8 @@ static int __init add_xo1_platform_devices(void)
 	return PTR_ERR_OR_ZERO(pdev);
 }
 
-static int olpc_xo1_ec_probe(struct platform_device *pdev)
-{
-	/* get the EC revision */
-	olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0,
-			(unsigned char *) &olpc_platform_info.ecver, 1);
-
-	/* EC version 0x5f adds support for wide SCI mask */
-	if (olpc_platform_info.ecver >= 0x5f)
-		olpc_platform_info.flags |= OLPC_F_EC_WIDE_SCI;
-
-	pr_info("OLPC board revision %s%X (EC=%x)\n",
-			((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
-			olpc_platform_info.boardrev >> 4,
-			olpc_platform_info.ecver);
-
-	return 0;
-}
 static int olpc_xo1_ec_suspend(struct platform_device *pdev)
 {
-	olpc_ec_mask_write(ec_wakeup_mask);
-
 	/*
 	 * Squelch SCIs while suspended.  This is a fix for
 	 * <http://dev.laptop.org/ticket/1835>.
@@ -359,15 +264,27 @@ static int olpc_xo1_ec_resume(struct platform_device *pdev)
 }
 
 static struct olpc_ec_driver ec_xo1_driver = {
-	.probe = olpc_xo1_ec_probe,
 	.suspend = olpc_xo1_ec_suspend,
 	.resume = olpc_xo1_ec_resume,
 	.ec_cmd = olpc_xo1_ec_cmd,
+#ifdef CONFIG_OLPC_XO1_SCI
+	/*
+	 * XO-1 EC wakeups are available when olpc-xo1-sci driver is
+	 * compiled in
+	 */
+	.wakeup_available = true,
+#endif
 };
 
 static struct olpc_ec_driver ec_xo1_5_driver = {
-	.probe = olpc_xo1_ec_probe,
 	.ec_cmd = olpc_xo1_ec_cmd,
+#ifdef CONFIG_OLPC_XO1_5_SCI
+	/*
+	 * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
+	 * compiled in
+	 */
+	.wakeup_available = true,
+#endif
 };
 
 static int __init olpc_init(void)
diff --git a/drivers/platform/olpc/olpc-ec.c b/drivers/platform/olpc/olpc-ec.c
index 981955dce926..2a647455a368 100644
--- a/drivers/platform/olpc/olpc-ec.c
+++ b/drivers/platform/olpc/olpc-ec.c
@@ -32,6 +32,7 @@ struct ec_cmd_desc {
 
 struct olpc_ec_priv {
 	struct olpc_ec_driver *drv;
+	u8 version;
 	struct work_struct worker;
 	struct mutex cmd_lock;
 
@@ -41,6 +42,12 @@ struct olpc_ec_priv {
 
 	struct dentry *dbgfs_dir;
 
+	/*
+	 * EC event mask to be applied during suspend (defining wakeup
+	 * sources).
+	 */
+	u16 ec_wakeup_mask;
+
 	/*
 	 * Running an EC command while suspending means we don't always finish
 	 * the command before the machine suspends.  This means that the EC
@@ -149,6 +156,88 @@ int olpc_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf, size_t outlen)
 }
 EXPORT_SYMBOL_GPL(olpc_ec_cmd);
 
+void olpc_ec_wakeup_set(u16 value)
+{
+	struct olpc_ec_priv *ec = ec_priv;
+
+	if (WARN_ON(!ec))
+		return;
+
+	ec->ec_wakeup_mask |= value;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set);
+
+void olpc_ec_wakeup_clear(u16 value)
+{
+	struct olpc_ec_priv *ec = ec_priv;
+
+	if (WARN_ON(!ec))
+		return;
+
+	ec->ec_wakeup_mask &= ~value;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear);
+
+int olpc_ec_mask_write(u16 bits)
+{
+	struct olpc_ec_priv *ec = ec_priv;
+
+	if (WARN_ON(!ec))
+		return -ENODEV;
+
+	/* EC version 0x5f adds support for wide SCI mask */
+	if (ec->version >= 0x5f) {
+		__be16 ec_word = cpu_to_be16(bits);
+
+		return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *)&ec_word, 2, NULL, 0);
+	} else {
+		u8 ec_byte = bits & 0xff;
+
+		return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0);
+	}
+}
+EXPORT_SYMBOL_GPL(olpc_ec_mask_write);
+
+/*
+ * Returns true if the compile and runtime configurations allow for EC events
+ * to wake the system.
+ */
+bool olpc_ec_wakeup_available(void)
+{
+	if (WARN_ON(!ec_driver))
+		return false;
+
+	return ec_driver->wakeup_available;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);
+
+int olpc_ec_sci_query(u16 *sci_value)
+{
+	struct olpc_ec_priv *ec = ec_priv;
+	int ret;
+
+	if (WARN_ON(!ec))
+		return -ENODEV;
+
+	/* EC version 0x5f adds support for wide SCI mask */
+	if (ec->version >= 0x5f) {
+		__be16 ec_word;
+
+		ret = olpc_ec_cmd(EC_EXT_SCI_QUERY, NULL, 0, (void *)&ec_word, 2);
+		if (ret == 0)
+			*sci_value = be16_to_cpu(ec_word);
+	} else {
+		u8 ec_byte;
+
+		ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1);
+		if (ret == 0)
+			*sci_value = ec_byte;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_sci_query);
+
 #ifdef CONFIG_DEBUG_FS
 
 /*
@@ -276,14 +365,16 @@ static int olpc_ec_probe(struct platform_device *pdev)
 	ec_priv = ec;
 	platform_set_drvdata(pdev, ec);
 
-	err = ec_driver->probe ? ec_driver->probe(pdev) : 0;
+	/* get the EC revision */
+	err = olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0, &ec->version, 1);
 	if (err) {
 		ec_priv = NULL;
 		kfree(ec);
-	} else {
-		ec->dbgfs_dir = olpc_ec_setup_debugfs();
+		return err;
 	}
 
+	ec->dbgfs_dir = olpc_ec_setup_debugfs();
+
 	return err;
 }
 
@@ -293,6 +384,8 @@ static int olpc_ec_suspend(struct device *dev)
 	struct olpc_ec_priv *ec = platform_get_drvdata(pdev);
 	int err = 0;
 
+	olpc_ec_mask_write(ec->ec_wakeup_mask);
+
 	if (ec_driver->suspend)
 		err = ec_driver->suspend(pdev);
 	if (!err)
diff --git a/drivers/power/supply/olpc_battery.c b/drivers/power/supply/olpc_battery.c
index c628d3a47e14..4ccd242fcf72 100644
--- a/drivers/power/supply/olpc_battery.c
+++ b/drivers/power/supply/olpc_battery.c
@@ -20,7 +20,6 @@
 #include <linux/jiffies.h>
 #include <linux/sched.h>
 #include <linux/olpc-ec.h>
-#include <asm/olpc.h>
 
 
 #define EC_BAT_VOLTAGE	0x10	/* uint16_t,	*9.76/32,    mV   */
diff --git a/include/linux/olpc-ec.h b/include/linux/olpc-ec.h
index 79bdc6328c52..7fa3d27f7fee 100644
--- a/include/linux/olpc-ec.h
+++ b/include/linux/olpc-ec.h
@@ -16,14 +16,28 @@
 #define EC_SCI_QUERY			0x84
 #define EC_EXT_SCI_QUERY		0x85
 
+/* SCI source values */
+#define EC_SCI_SRC_EMPTY        0x00
+#define EC_SCI_SRC_GAME         0x01
+#define EC_SCI_SRC_BATTERY      0x02
+#define EC_SCI_SRC_BATSOC       0x04
+#define EC_SCI_SRC_BATERR       0x08
+#define EC_SCI_SRC_EBOOK        0x10    /* XO-1 only */
+#define EC_SCI_SRC_WLAN         0x20    /* XO-1 only */
+#define EC_SCI_SRC_ACPWR        0x40
+#define EC_SCI_SRC_BATCRIT      0x80
+#define EC_SCI_SRC_GPWAKE       0x100   /* XO-1.5 only */
+#define EC_SCI_SRC_ALL          0x1FF
+
 struct platform_device;
 
 struct olpc_ec_driver {
-	int (*probe)(struct platform_device *);
 	int (*suspend)(struct platform_device *);
 	int (*resume)(struct platform_device *);
 
 	int (*ec_cmd)(u8, u8 *, size_t, u8 *, size_t, void *);
+
+	bool wakeup_available;
 };
 
 #ifdef CONFIG_OLPC
@@ -33,11 +47,27 @@ extern void olpc_ec_driver_register(struct olpc_ec_driver *drv, void *arg);
 extern int olpc_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf,
 		size_t outlen);
 
+extern void olpc_ec_wakeup_set(u16 value);
+extern void olpc_ec_wakeup_clear(u16 value);
+
+extern int olpc_ec_mask_write(u16 bits);
+extern int olpc_ec_sci_query(u16 *sci_value);
+
+extern bool olpc_ec_wakeup_available(void);
+
 #else
 
 static inline int olpc_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf,
 		size_t outlen) { return -ENODEV; }
 
+static inline void olpc_ec_wakeup_set(u16 value) { }
+static inline void olpc_ec_wakeup_clear(u16 value) { }
+
+static inline bool olpc_ec_wakeup_available(void)
+{
+	return false;
+}
+
 #endif /* CONFIG_OLPC */
 
 #endif /* _LINUX_OLPC_EC_H */
-- 
2.21.0

[PATCH v7 04/10] Platform: OLPC: Avoid a warning if the EC didn't register yet

[Lubomir Rintel]

Just return EPROBE_DEFER, so that whoever attempted to use the EC call can
defer their work.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>

---
Changes since v2:
- Adjust the commit message for the s/ENODEV/EPROBE_DEFER/ change

Changes since v1:
- EPROBE_DEFER instead of ENODEV

 drivers/platform/olpc/olpc-ec.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/olpc/olpc-ec.c b/drivers/platform/olpc/olpc-ec.c
index 2a647455a368..a91f78245f5e 100644
--- a/drivers/platform/olpc/olpc-ec.c
+++ b/drivers/platform/olpc/olpc-ec.c
@@ -125,8 +125,11 @@ int olpc_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf, size_t outlen)
 	struct olpc_ec_priv *ec = ec_priv;
 	struct ec_cmd_desc desc;
 
-	/* Ensure a driver and ec hook have been registered */
-	if (WARN_ON(!ec_driver || !ec_driver->ec_cmd))
+	/* Driver not yet registered. */
+	if (!ec_driver)
+		return -EPROBE_DEFER;
+
+	if (WARN_ON(!ec_driver->ec_cmd))
 		return -ENODEV;
 
 	if (!ec)
-- 
2.21.0

[PATCH v7 05/10] Platform: OLPC: Use BIT() and GENMASK() for event masks

[Lubomir Rintel]

Just a cosmetic tidy-up.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

---
Changes since v5:
- Added Andy Shevchenko's Reviewed-by tag

Changes since v1:
- This patch was added to the set.

 include/linux/olpc-ec.h | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/include/linux/olpc-ec.h b/include/linux/olpc-ec.h
index 7fa3d27f7fee..f7b6a7eda232 100644
--- a/include/linux/olpc-ec.h
+++ b/include/linux/olpc-ec.h
@@ -2,6 +2,8 @@
 #ifndef _LINUX_OLPC_EC_H
 #define _LINUX_OLPC_EC_H
 
+#include <linux/bits.h>
+
 /* XO-1 EC commands */
 #define EC_FIRMWARE_REV			0x08
 #define EC_WRITE_SCI_MASK		0x1b
@@ -17,17 +19,16 @@
 #define EC_EXT_SCI_QUERY		0x85
 
 /* SCI source values */
-#define EC_SCI_SRC_EMPTY        0x00
-#define EC_SCI_SRC_GAME         0x01
-#define EC_SCI_SRC_BATTERY      0x02
-#define EC_SCI_SRC_BATSOC       0x04
-#define EC_SCI_SRC_BATERR       0x08
-#define EC_SCI_SRC_EBOOK        0x10    /* XO-1 only */
-#define EC_SCI_SRC_WLAN         0x20    /* XO-1 only */
-#define EC_SCI_SRC_ACPWR        0x40
-#define EC_SCI_SRC_BATCRIT      0x80
-#define EC_SCI_SRC_GPWAKE       0x100   /* XO-1.5 only */
-#define EC_SCI_SRC_ALL          0x1FF
+#define EC_SCI_SRC_GAME         BIT(0)
+#define EC_SCI_SRC_BATTERY      BIT(1)
+#define EC_SCI_SRC_BATSOC       BIT(2)
+#define EC_SCI_SRC_BATERR       BIT(3)
+#define EC_SCI_SRC_EBOOK        BIT(4)    /* XO-1 only */
+#define EC_SCI_SRC_WLAN         BIT(5)    /* XO-1 only */
+#define EC_SCI_SRC_ACPWR        BIT(6)
+#define EC_SCI_SRC_BATCRIT      BIT(7)
+#define EC_SCI_SRC_GPWAKE       BIT(8)   /* XO-1.5 only */
+#define EC_SCI_SRC_ALL          GENMASK(8, 0)
 
 struct platform_device;
 
-- 
2.21.0

[PATCH v7 06/10] Platform: OLPC: Add XO-1.75 EC driver

[Lubomir Rintel]

It's based off the driver from the OLPC kernel sources. Somewhat
modernized and cleaned up, for better or worse.

Modified to plug into the olpc-ec driver infrastructure (so that battery
interface and debugfs could be reused) and the SPI slave framework.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

---
Changes since v6:
- s/%d/%zd/ for size_t, to avoid a compiler warning upon COMPILE_TEST on
  64bit, discovered by kbuild bot
- rename olpc_xo175_ec_is_valid_cmd() to olpc_xo175_ec_resp_len() to match
  what it actually does; cast its result to size_t once checked, to address
  a warning reported by Julia Lawall and kbuild bot with smatch

Changes since v5:
- Collected Andy Shevchenko's Reviewed-by tag
- s/unsigned char/u8/, drop an unnecessary "& 0xff"

Changes since v4:
- Chop off the reboot handler. Will be added back once it's clear how.

Changes since v3:
- Introduce CONFIG_OLPC_EC symbol to enable parts common to this driver
  and the X86 OLPC EC machinery.

Changes since v1:
- Cosmetic style changes; whitespace, ordering of declarations and
  #includes, remoted extra comas from sentinels
- Count the terminating NUL in LOG_BUF_SIZE
- Make olpc_xo175_ec_is_valid_cmd() return -EINVAL instead of -1
  on error
- Spell keyboard/touchpad in full for CHAN_KEYBOARD/TOUCHPAD messages
- Use a #define for PM wakeup processing time
- Log a message on unknown event
- Escape logging payload with %*pE
- Replace an open-coded min()
- Correct an error code on short read
- replaced PM callback #ifdefs with __maybe_unusedm SET_RUNTIME_PM_OPS
  and SET_NOIRQ_SYSTEM_SLEEP_PM_OPS
- dev_get_drvdata() instead of a round-trip through platform device
- s/unsigned char x/u8 x/ in olpc_xo175_ec_resume()
- Use GENMASK() instead of 0xffff for the event mask
- Replace cmd tx/resp rx buffers with structures
- Turned suspend hint arguments into a struct, and tidied up the comment

Basically all of the above is based on the review by Andy Shevchenko.

 arch/x86/Kconfig                      |   1 +
 drivers/platform/Kconfig              |   2 +
 drivers/platform/Makefile             |   2 +-
 drivers/platform/olpc/Kconfig         |  14 +
 drivers/platform/olpc/Makefile        |   3 +-
 drivers/platform/olpc/olpc-xo175-ec.c | 752 ++++++++++++++++++++++++++
 include/linux/olpc-ec.h               |   4 +-
 7 files changed, 774 insertions(+), 4 deletions(-)
 create mode 100644 drivers/platform/olpc/Kconfig
 create mode 100644 drivers/platform/olpc/olpc-xo175-ec.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c1f9b3cf437c..7dde8ddd08db 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2710,6 +2710,7 @@ config OLPC
 	select OF
 	select OF_PROMTREE
 	select IRQ_DOMAIN
+	select OLPC_EC
 	---help---
 	  Add support for detecting the unique features of the OLPC
 	  XO hardware.
diff --git a/drivers/platform/Kconfig b/drivers/platform/Kconfig
index d4c2e424a700..4313d73d3618 100644
--- a/drivers/platform/Kconfig
+++ b/drivers/platform/Kconfig
@@ -10,3 +10,5 @@ source "drivers/platform/goldfish/Kconfig"
 source "drivers/platform/chrome/Kconfig"
 
 source "drivers/platform/mellanox/Kconfig"
+
+source "drivers/platform/olpc/Kconfig"
diff --git a/drivers/platform/Makefile b/drivers/platform/Makefile
index 4b2ce58bcd9c..6fda58c021ca 100644
--- a/drivers/platform/Makefile
+++ b/drivers/platform/Makefile
@@ -6,6 +6,6 @@
 obj-$(CONFIG_X86)		+= x86/
 obj-$(CONFIG_MELLANOX_PLATFORM)	+= mellanox/
 obj-$(CONFIG_MIPS)		+= mips/
-obj-$(CONFIG_OLPC)		+= olpc/
+obj-$(CONFIG_OLPC_EC)		+= olpc/
 obj-$(CONFIG_GOLDFISH)		+= goldfish/
 obj-$(CONFIG_CHROME_PLATFORMS)	+= chrome/
diff --git a/drivers/platform/olpc/Kconfig b/drivers/platform/olpc/Kconfig
new file mode 100644
index 000000000000..559f843199d7
--- /dev/null
+++ b/drivers/platform/olpc/Kconfig
@@ -0,0 +1,14 @@
+config OLPC_EC
+	bool
+
+config OLPC_XO175_EC
+	tristate "OLPC XO 1.75 Embedded Controller"
+	depends on ARCH_MMP || COMPILE_TEST
+	select SPI_SLAVE
+	select OLPC_EC
+	help
+	  Include support for the OLPC XO Embedded Controller (EC). The EC
+	  provides various platform services, including support for the power,
+	  button, restart, shutdown and battery charging status.
+
+	  Unless you have an OLPC XO laptop, you will want to say N.
diff --git a/drivers/platform/olpc/Makefile b/drivers/platform/olpc/Makefile
index dc8b26bc7209..01fe6ba01665 100644
--- a/drivers/platform/olpc/Makefile
+++ b/drivers/platform/olpc/Makefile
@@ -1,4 +1,5 @@
 #
 # OLPC XO platform-specific drivers
 #
-obj-$(CONFIG_OLPC)		+= olpc-ec.o
+obj-$(CONFIG_OLPC_EC)		+= olpc-ec.o
+obj-$(CONFIG_OLPC_XO175_EC)	+= olpc-xo175-ec.o
diff --git a/drivers/platform/olpc/olpc-xo175-ec.c b/drivers/platform/olpc/olpc-xo175-ec.c
new file mode 100644
index 000000000000..344d14f3da54
--- /dev/null
+++ b/drivers/platform/olpc/olpc-xo175-ec.c
@@ -0,0 +1,752 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for the OLPC XO-1.75 Embedded Controller.
+ *
+ * The EC protocol is documented at:
+ * http://wiki.laptop.org/go/XO_1.75_HOST_to_EC_Protocol
+ *
+ * Copyright (C) 2010 One Laptop per Child Foundation.
+ * Copyright (C) 2018 Lubomir Rintel <lkundrak@v3.sk>
+ */
+
+#include <linux/completion.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/input.h>
+#include <linux/kfifo.h>
+#include <linux/module.h>
+#include <linux/olpc-ec.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/spi/spi.h>
+
+struct ec_cmd_t {
+	u8 cmd;
+	u8 bytes_returned;
+};
+
+enum ec_chan_t {
+	CHAN_NONE = 0,
+	CHAN_SWITCH,
+	CHAN_CMD_RESP,
+	CHAN_KEYBOARD,
+	CHAN_TOUCHPAD,
+	CHAN_EVENT,
+	CHAN_DEBUG,
+	CHAN_CMD_ERROR,
+};
+
+/*
+ * EC events
+ */
+#define EVENT_AC_CHANGE			1  /* AC plugged/unplugged */
+#define EVENT_BATTERY_STATUS		2  /* Battery low/full/error/gone */
+#define EVENT_BATTERY_CRITICAL		3  /* Battery critical voltage */
+#define EVENT_BATTERY_SOC_CHANGE	4  /* 1% SOC Change */
+#define EVENT_BATTERY_ERROR		5  /* Abnormal error, query for cause */
+#define EVENT_POWER_PRESSED		6  /* Power button was pressed */
+#define EVENT_POWER_PRESS_WAKE		7  /* Woken up with a power button */
+#define EVENT_TIMED_HOST_WAKE		8  /* Host wake timer */
+#define EVENT_OLS_HIGH_LIMIT		9  /* OLS crossed dark threshold */
+#define EVENT_OLS_LOW_LIMIT		10 /* OLS crossed light threshold */
+
+/*
+ * EC commands
+ * (from http://dev.laptop.org/git/users/rsmith/ec-1.75/tree/ec_cmd.h)
+ */
+#define CMD_GET_API_VERSION		0x08 /* out: u8 */
+#define CMD_READ_VOLTAGE		0x10 /* out: u16, *9.76/32, mV */
+#define CMD_READ_CURRENT		0x11 /* out: s16, *15.625/120, mA */
+#define CMD_READ_ACR			0x12 /* out: s16, *6250/15, uAh */
+#define CMD_READ_BATT_TEMPERATURE	0x13 /* out: u16, *100/256, deg C */
+#define CMD_READ_AMBIENT_TEMPERATURE	0x14 /* unimplemented, no hardware */
+#define CMD_READ_BATTERY_STATUS		0x15 /* out: u8, bitmask */
+#define CMD_READ_SOC			0x16 /* out: u8, percentage */
+#define CMD_READ_GAUGE_ID		0x17 /* out: u8 * 8 */
+#define CMD_READ_GAUGE_DATA		0x18 /* in: u8 addr, out: u8 data */
+#define CMD_READ_BOARD_ID		0x19 /* out: u16 (platform id) */
+#define CMD_READ_BATT_ERR_CODE		0x1f /* out: u8, error bitmask */
+#define CMD_SET_DCON_POWER		0x26 /* in: u8 */
+#define CMD_RESET_EC			0x28 /* none */
+#define CMD_READ_BATTERY_TYPE		0x2c /* out: u8 */
+#define CMD_SET_AUTOWAK			0x33 /* out: u8 */
+#define CMD_SET_EC_WAKEUP_TIMER		0x36 /* in: u32, out: ? */
+#define CMD_READ_EXT_SCI_MASK		0x37 /* ? */
+#define CMD_WRITE_EXT_SCI_MASK		0x38 /* ? */
+#define CMD_CLEAR_EC_WAKEUP_TIMER	0x39 /* none */
+#define CMD_ENABLE_RUNIN_DISCHARGE	0x3B /* none */
+#define CMD_DISABLE_RUNIN_DISCHARGE	0x3C /* none */
+#define CMD_READ_MPPT_ACTIVE		0x3d /* out: u8 */
+#define CMD_READ_MPPT_LIMIT		0x3e /* out: u8 */
+#define CMD_SET_MPPT_LIMIT		0x3f /* in: u8 */
+#define CMD_DISABLE_MPPT		0x40 /* none */
+#define CMD_ENABLE_MPPT			0x41 /* none */
+#define CMD_READ_VIN			0x42 /* out: u16 */
+#define CMD_EXT_SCI_QUERY		0x43 /* ? */
+#define RSP_KEYBOARD_DATA		0x48 /* ? */
+#define RSP_TOUCHPAD_DATA		0x49 /* ? */
+#define CMD_GET_FW_VERSION		0x4a /* out: u8 * 16 */
+#define CMD_POWER_CYCLE			0x4b /* none */
+#define CMD_POWER_OFF			0x4c /* none */
+#define CMD_RESET_EC_SOFT		0x4d /* none */
+#define CMD_READ_GAUGE_U16		0x4e /* ? */
+#define CMD_ENABLE_MOUSE		0x4f /* ? */
+#define CMD_ECHO			0x52 /* in: u8 * 5, out: u8 * 5 */
+#define CMD_GET_FW_DATE			0x53 /* out: u8 * 16 */
+#define CMD_GET_FW_USER			0x54 /* out: u8 * 16 */
+#define CMD_TURN_OFF_POWER		0x55 /* none (same as 0x4c) */
+#define CMD_READ_OLS			0x56 /* out: u16 */
+#define CMD_OLS_SMT_LEDON		0x57 /* none */
+#define CMD_OLS_SMT_LEDOFF		0x58 /* none */
+#define CMD_START_OLS_ASSY		0x59 /* none */
+#define CMD_STOP_OLS_ASSY		0x5a /* none */
+#define CMD_OLS_SMTTEST_STOP		0x5b /* none */
+#define CMD_READ_VIN_SCALED		0x5c /* out: u16 */
+#define CMD_READ_BAT_MIN_W		0x5d /* out: u16 */
+#define CMD_READ_BAR_MAX_W		0x5e /* out: u16 */
+#define CMD_RESET_BAT_MINMAX_W		0x5f /* none */
+#define CMD_READ_LOCATION		0x60 /* in: u16 addr, out: u8 data */
+#define CMD_WRITE_LOCATION		0x61 /* in: u16 addr, u8 data */
+#define CMD_KEYBOARD_CMD		0x62 /* in: u8, out: ? */
+#define CMD_TOUCHPAD_CMD		0x63 /* in: u8, out: ? */
+#define CMD_GET_FW_HASH			0x64 /* out: u8 * 16 */
+#define CMD_SUSPEND_HINT		0x65 /* in: u8 */
+#define CMD_ENABLE_WAKE_TIMER		0x66 /* in: u8 */
+#define CMD_SET_WAKE_TIMER		0x67 /* in: 32 */
+#define CMD_ENABLE_WAKE_AUTORESET	0x68 /* in: u8 */
+#define CMD_OLS_SET_LIMITS		0x69 /* in: u16, u16 */
+#define CMD_OLS_GET_LIMITS		0x6a /* out: u16, u16 */
+#define CMD_OLS_SET_CEILING		0x6b /* in: u16 */
+#define CMD_OLS_GET_CEILING		0x6c /* out: u16 */
+
+/*
+ * Accepted EC commands, and how many bytes they return. There are plenty
+ * of EC commands that are no longer implemented, or are implemented only on
+ * certain older boards.
+ */
+static const struct ec_cmd_t olpc_xo175_ec_cmds[] = {
+	{ CMD_GET_API_VERSION, 1 },
+	{ CMD_READ_VOLTAGE, 2 },
+	{ CMD_READ_CURRENT, 2 },
+	{ CMD_READ_ACR, 2 },
+	{ CMD_READ_BATT_TEMPERATURE, 2 },
+	{ CMD_READ_BATTERY_STATUS, 1 },
+	{ CMD_READ_SOC, 1 },
+	{ CMD_READ_GAUGE_ID, 8 },
+	{ CMD_READ_GAUGE_DATA, 1 },
+	{ CMD_READ_BOARD_ID, 2 },
+	{ CMD_READ_BATT_ERR_CODE, 1 },
+	{ CMD_SET_DCON_POWER, 0 },
+	{ CMD_RESET_EC, 0 },
+	{ CMD_READ_BATTERY_TYPE, 1 },
+	{ CMD_ENABLE_RUNIN_DISCHARGE, 0 },
+	{ CMD_DISABLE_RUNIN_DISCHARGE, 0 },
+	{ CMD_READ_MPPT_ACTIVE, 1 },
+	{ CMD_READ_MPPT_LIMIT, 1 },
+	{ CMD_SET_MPPT_LIMIT, 0 },
+	{ CMD_DISABLE_MPPT, 0 },
+	{ CMD_ENABLE_MPPT, 0 },
+	{ CMD_READ_VIN, 2 },
+	{ CMD_GET_FW_VERSION, 16 },
+	{ CMD_POWER_CYCLE, 0 },
+	{ CMD_POWER_OFF, 0 },
+	{ CMD_RESET_EC_SOFT, 0 },
+	{ CMD_ECHO, 5 },
+	{ CMD_GET_FW_DATE, 16 },
+	{ CMD_GET_FW_USER, 16 },
+	{ CMD_TURN_OFF_POWER, 0 },
+	{ CMD_READ_OLS, 2 },
+	{ CMD_OLS_SMT_LEDON, 0 },
+	{ CMD_OLS_SMT_LEDOFF, 0 },
+	{ CMD_START_OLS_ASSY, 0 },
+	{ CMD_STOP_OLS_ASSY, 0 },
+	{ CMD_OLS_SMTTEST_STOP, 0 },
+	{ CMD_READ_VIN_SCALED, 2 },
+	{ CMD_READ_BAT_MIN_W, 2 },
+	{ CMD_READ_BAR_MAX_W, 2 },
+	{ CMD_RESET_BAT_MINMAX_W, 0 },
+	{ CMD_READ_LOCATION, 1 },
+	{ CMD_WRITE_LOCATION, 0 },
+	{ CMD_GET_FW_HASH, 16 },
+	{ CMD_SUSPEND_HINT, 0 },
+	{ CMD_ENABLE_WAKE_TIMER, 0 },
+	{ CMD_SET_WAKE_TIMER, 0 },
+	{ CMD_ENABLE_WAKE_AUTORESET, 0 },
+	{ CMD_OLS_SET_LIMITS, 0 },
+	{ CMD_OLS_GET_LIMITS, 4 },
+	{ CMD_OLS_SET_CEILING, 0 },
+	{ CMD_OLS_GET_CEILING, 2 },
+	{ CMD_READ_EXT_SCI_MASK, 2 },
+	{ CMD_WRITE_EXT_SCI_MASK, 0 },
+
+	{ }
+};
+
+#define EC_MAX_CMD_DATA_LEN	5
+#define EC_MAX_RESP_LEN		16
+
+#define LOG_BUF_SIZE		128
+
+#define PM_WAKEUP_TIME		1000
+
+#define EC_ALL_EVENTS		GENMASK(15, 0)
+
+enum ec_state_t {
+	CMD_STATE_IDLE = 0,
+	CMD_STATE_WAITING_FOR_SWITCH,
+	CMD_STATE_CMD_IN_TX_FIFO,
+	CMD_STATE_CMD_SENT,
+	CMD_STATE_RESP_RECEIVED,
+	CMD_STATE_ERROR_RECEIVED,
+};
+
+struct olpc_xo175_ec_cmd {
+	u8 command;
+	u8 nr_args;
+	u8 data_len;
+	u8 args[EC_MAX_CMD_DATA_LEN];
+};
+
+struct olpc_xo175_ec_resp {
+	u8 channel;
+	u8 byte;
+};
+
+struct olpc_xo175_ec {
+	bool suspended;
+
+	/* SPI related stuff. */
+	struct spi_device *spi;
+	struct spi_transfer xfer;
+	struct spi_message msg;
+	union {
+		struct olpc_xo175_ec_cmd cmd;
+		struct olpc_xo175_ec_resp resp;
+	} tx_buf, rx_buf;
+
+	/* GPIO for the CMD signals. */
+	struct gpio_desc *gpio_cmd;
+
+	/* Command handling related state. */
+	spinlock_t cmd_state_lock;
+	int cmd_state;
+	bool cmd_running;
+	struct completion cmd_done;
+	struct olpc_xo175_ec_cmd cmd;
+	u8 resp_data[EC_MAX_RESP_LEN];
+	int expected_resp_len;
+	int resp_len;
+
+	/* Power button. */
+	struct input_dev *pwrbtn;
+
+	/* Debug handling. */
+	char logbuf[LOG_BUF_SIZE];
+	int logbuf_len;
+};
+
+static struct platform_device *olpc_ec;
+
+static int olpc_xo175_ec_resp_len(u8 cmd)
+{
+	const struct ec_cmd_t *p;
+
+	for (p = olpc_xo175_ec_cmds; p->cmd; p++) {
+		if (p->cmd == cmd)
+			return p->bytes_returned;
+	}
+
+	return -EINVAL;
+}
+
+static void olpc_xo175_ec_flush_logbuf(struct olpc_xo175_ec *priv)
+{
+	dev_dbg(&priv->spi->dev, "got debug string [%*pE]\n",
+				priv->logbuf_len, priv->logbuf);
+	priv->logbuf_len = 0;
+}
+
+static void olpc_xo175_ec_complete(void *arg);
+
+static void olpc_xo175_ec_send_command(struct olpc_xo175_ec *priv, void *cmd,
+								size_t cmdlen)
+{
+	int ret;
+
+	memcpy(&priv->tx_buf, cmd, cmdlen);
+	priv->xfer.len = cmdlen;
+
+	spi_message_init_with_transfers(&priv->msg, &priv->xfer, 1);
+
+	priv->msg.complete = olpc_xo175_ec_complete;
+	priv->msg.context = priv;
+
+	ret = spi_async(priv->spi, &priv->msg);
+	if (ret)
+		dev_err(&priv->spi->dev, "spi_async() failed %d\n", ret);
+}
+
+static void olpc_xo175_ec_read_packet(struct olpc_xo175_ec *priv)
+{
+	u8 nonce[] = {0xA5, 0x5A};
+
+	olpc_xo175_ec_send_command(priv, nonce, sizeof(nonce));
+}
+
+static void olpc_xo175_ec_complete(void *arg)
+{
+	struct olpc_xo175_ec *priv = arg;
+	struct device *dev = &priv->spi->dev;
+	struct power_supply *psy;
+	unsigned long flags;
+	u8 channel;
+	u8 byte;
+	int ret;
+
+	ret = priv->msg.status;
+	if (ret) {
+		dev_err(dev, "SPI transfer failed: %d\n", ret);
+
+		spin_lock_irqsave(&priv->cmd_state_lock, flags);
+		if (priv->cmd_running) {
+			priv->resp_len = 0;
+			priv->cmd_state = CMD_STATE_ERROR_RECEIVED;
+			complete(&priv->cmd_done);
+		}
+		spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+
+		if (ret != -EINTR)
+			olpc_xo175_ec_read_packet(priv);
+
+		return;
+	}
+
+	channel = priv->rx_buf.resp.channel;
+	byte = priv->rx_buf.resp.byte;
+
+	switch (channel) {
+	case CHAN_NONE:
+		spin_lock_irqsave(&priv->cmd_state_lock, flags);
+
+		if (!priv->cmd_running) {
+			/* We can safely ignore these */
+			dev_err(dev, "spurious FIFO read packet\n");
+			spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+			return;
+		}
+
+		priv->cmd_state = CMD_STATE_CMD_SENT;
+		if (!priv->expected_resp_len)
+			complete(&priv->cmd_done);
+		olpc_xo175_ec_read_packet(priv);
+
+		spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+		return;
+
+	case CHAN_SWITCH:
+		spin_lock_irqsave(&priv->cmd_state_lock, flags);
+
+		if (!priv->cmd_running) {
+			/* Just go with the flow */
+			dev_err(dev, "spurious SWITCH packet\n");
+			memset(&priv->cmd, 0, sizeof(priv->cmd));
+			priv->cmd.command = CMD_ECHO;
+		}
+
+		priv->cmd_state = CMD_STATE_CMD_IN_TX_FIFO;
+
+		/* Throw command into TxFIFO */
+		gpiod_set_value_cansleep(priv->gpio_cmd, 0);
+		olpc_xo175_ec_send_command(priv, &priv->cmd, sizeof(priv->cmd));
+
+		spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+		return;
+
+	case CHAN_CMD_RESP:
+		spin_lock_irqsave(&priv->cmd_state_lock, flags);
+
+		if (!priv->cmd_running) {
+			dev_err(dev, "spurious response packet\n");
+		} else if (priv->resp_len >= priv->expected_resp_len) {
+			dev_err(dev, "too many response packets\n");
+		} else {
+			priv->resp_data[priv->resp_len++] = byte;
+			if (priv->resp_len == priv->expected_resp_len) {
+				priv->cmd_state = CMD_STATE_RESP_RECEIVED;
+				complete(&priv->cmd_done);
+			}
+		}
+
+		spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+		break;
+
+	case CHAN_CMD_ERROR:
+		spin_lock_irqsave(&priv->cmd_state_lock, flags);
+
+		if (!priv->cmd_running) {
+			dev_err(dev, "spurious cmd error packet\n");
+		} else {
+			priv->resp_data[0] = byte;
+			priv->resp_len = 1;
+			priv->cmd_state = CMD_STATE_ERROR_RECEIVED;
+			complete(&priv->cmd_done);
+		}
+		spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+		break;
+
+	case CHAN_KEYBOARD:
+		dev_warn(dev, "keyboard is not supported\n");
+		break;
+
+	case CHAN_TOUCHPAD:
+		dev_warn(dev, "touchpad is not supported\n");
+		break;
+
+	case CHAN_EVENT:
+		dev_dbg(dev, "got event %.2x\n", byte);
+		switch (byte) {
+		case EVENT_AC_CHANGE:
+			psy = power_supply_get_by_name("olpc-ac");
+			if (psy) {
+				power_supply_changed(psy);
+				power_supply_put(psy);
+			}
+			break;
+		case EVENT_BATTERY_STATUS:
+		case EVENT_BATTERY_CRITICAL:
+		case EVENT_BATTERY_SOC_CHANGE:
+		case EVENT_BATTERY_ERROR:
+			psy = power_supply_get_by_name("olpc-battery");
+			if (psy) {
+				power_supply_changed(psy);
+				power_supply_put(psy);
+			}
+			break;
+		case EVENT_POWER_PRESSED:
+			input_report_key(priv->pwrbtn, KEY_POWER, 1);
+			input_sync(priv->pwrbtn);
+			input_report_key(priv->pwrbtn, KEY_POWER, 0);
+			input_sync(priv->pwrbtn);
+			/* fall through */
+		case EVENT_POWER_PRESS_WAKE:
+		case EVENT_TIMED_HOST_WAKE:
+			pm_wakeup_event(priv->pwrbtn->dev.parent,
+						PM_WAKEUP_TIME);
+			break;
+		default:
+			dev_dbg(dev, "ignored unknown event %.2x\n", byte);
+			break;
+		}
+		break;
+
+	case CHAN_DEBUG:
+		if (byte == '\n') {
+			olpc_xo175_ec_flush_logbuf(priv);
+		} else if (isprint(byte)) {
+			priv->logbuf[priv->logbuf_len++] = byte;
+			if (priv->logbuf_len == LOG_BUF_SIZE)
+				olpc_xo175_ec_flush_logbuf(priv);
+		}
+		break;
+
+	default:
+		dev_warn(dev, "unknown channel: %d, %.2x\n", channel, byte);
+		break;
+	}
+
+	/* Most non-command packets get the TxFIFO refilled and an ACK. */
+	olpc_xo175_ec_read_packet(priv);
+}
+
+/*
+ * This function is protected with a mutex. We can safely assume that
+ * there will be only one instance of this function running at a time.
+ * One of the ways in which we enforce this is by waiting until we get
+ * all response bytes back from the EC, rather than just the number that
+ * the caller requests (otherwise, we might start a new command while an
+ * old command's response bytes are still incoming).
+ */
+static int olpc_xo175_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *resp,
+					size_t resp_len, void *ec_cb_arg)
+{
+	struct olpc_xo175_ec *priv = ec_cb_arg;
+	struct device *dev = &priv->spi->dev;
+	unsigned long flags;
+	size_t nr_bytes;
+	int ret = 0;
+
+	dev_dbg(dev, "CMD %x, %zd bytes expected\n", cmd, resp_len);
+
+	if (inlen > 5) {
+		dev_err(dev, "command len %zd too big!\n", resp_len);
+		return -EOVERFLOW;
+	}
+
+	/* Suspending in the middle of an EC command hoses things badly! */
+	if (WARN_ON(priv->suspended))
+		return -EBUSY;
+
+	/* Ensure a valid command and return bytes */
+	ret = olpc_xo175_ec_resp_len(cmd);
+	if (ret < 0) {
+		dev_err_ratelimited(dev, "unknown command 0x%x\n", cmd);
+
+		/*
+		 * Assume the best in our callers, and allow unknown commands
+		 * through. I'm not the charitable type, but it was beaten
+		 * into me. Just maintain a minimum standard of sanity.
+		 */
+		if (resp_len > sizeof(priv->resp_data)) {
+			dev_err(dev, "response too big: %zd!\n", resp_len);
+			return -EOVERFLOW;
+		}
+		nr_bytes = resp_len;
+	} else {
+		nr_bytes = (size_t)ret;
+	}
+	resp_len = min(resp_len, nr_bytes);
+
+	spin_lock_irqsave(&priv->cmd_state_lock, flags);
+
+	/* Initialize the state machine */
+	init_completion(&priv->cmd_done);
+	priv->cmd_running = true;
+	priv->cmd_state = CMD_STATE_WAITING_FOR_SWITCH;
+	memset(&priv->cmd, 0, sizeof(priv->cmd));
+	priv->cmd.command = cmd;
+	priv->cmd.nr_args = inlen;
+	priv->cmd.data_len = 0;
+	memcpy(priv->cmd.args, inbuf, inlen);
+	priv->expected_resp_len = nr_bytes;
+	priv->resp_len = 0;
+
+	/* Tickle the cmd gpio to get things started */
+	gpiod_set_value_cansleep(priv->gpio_cmd, 1);
+
+	spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+
+	/* The irq handler should do the rest */
+	if (!wait_for_completion_timeout(&priv->cmd_done,
+			msecs_to_jiffies(4000))) {
+		dev_err(dev, "EC cmd error: timeout in STATE %d\n",
+				priv->cmd_state);
+		gpiod_set_value_cansleep(priv->gpio_cmd, 0);
+		spi_slave_abort(priv->spi);
+		olpc_xo175_ec_read_packet(priv);
+		return -ETIMEDOUT;
+	}
+
+	spin_lock_irqsave(&priv->cmd_state_lock, flags);
+
+	/* Deal with the results. */
+	if (priv->cmd_state == CMD_STATE_ERROR_RECEIVED) {
+		/* EC-provided error is in the single response byte */
+		dev_err(dev, "command 0x%x returned error 0x%x\n",
+						cmd, priv->resp_data[0]);
+		ret = -EREMOTEIO;
+	} else if (priv->resp_len != nr_bytes) {
+		dev_err(dev, "command 0x%x returned %d bytes, expected %zd bytes\n",
+						cmd, priv->resp_len, nr_bytes);
+		ret = -EREMOTEIO;
+	} else {
+		/*
+		 * We may have 8 bytes in priv->resp, but we only care about
+		 * what we've been asked for. If the caller asked for only 2
+		 * bytes, give them that. We've guaranteed that
+		 * resp_len <= priv->resp_len and priv->resp_len == nr_bytes.
+		 */
+		memcpy(resp, priv->resp_data, resp_len);
+	}
+
+	/* This should already be low, but just in case. */
+	gpiod_set_value_cansleep(priv->gpio_cmd, 0);
+	priv->cmd_running = false;
+
+	spin_unlock_irqrestore(&priv->cmd_state_lock, flags);
+
+	return ret;
+}
+
+static int olpc_xo175_ec_set_event_mask(unsigned int mask)
+{
+	u8 args[2];
+
+	args[0] = mask >> 0;
+	args[1] = mask >> 8;
+	return olpc_ec_cmd(CMD_WRITE_EXT_SCI_MASK, args, 2, NULL, 0);
+}
+
+static void olpc_xo175_ec_power_off(void)
+{
+	while (1) {
+		olpc_ec_cmd(CMD_POWER_OFF, NULL, 0, NULL, 0);
+		mdelay(1000);
+	}
+}
+
+static int __maybe_unused olpc_xo175_ec_suspend(struct device *dev)
+{
+	struct olpc_xo175_ec *priv = dev_get_drvdata(dev);
+	static struct {
+		u8 suspend;
+		u32 suspend_count;
+	} __packed hintargs;
+	static unsigned int suspend_count;
+
+	/*
+	 * SOC_SLEEP is not wired to the EC on B3 and earlier boards.
+	 * This command lets the EC know instead. The suspend count doesn't seem
+	 * to be used anywhere but in the EC debug output.
+	 */
+	hintargs.suspend = 1;
+	hintargs.suspend_count = suspend_count++;
+	olpc_ec_cmd(CMD_SUSPEND_HINT, (void *)&hintargs, sizeof(hintargs),
+								NULL, 0);
+
+	/*
+	 * After we've sent the suspend hint, don't allow further EC commands
+	 * to be run until we've resumed. Userspace tasks should be frozen,
+	 * but kernel threads and interrupts could still schedule EC commands.
+	 */
+	priv->suspended = true;
+
+	return 0;
+}
+
+static int __maybe_unused olpc_xo175_ec_resume_noirq(struct device *dev)
+{
+	struct olpc_xo175_ec *priv = dev_get_drvdata(dev);
+
+	priv->suspended = false;
+
+	return 0;
+}
+
+static int __maybe_unused olpc_xo175_ec_resume(struct device *dev)
+{
+	u8 x = 0;
+
+	/*
+	 * The resume hint is only needed if no other commands are
+	 * being sent during resume. all it does is tell the EC
+	 * the SoC is definitely awake.
+	 */
+	olpc_ec_cmd(CMD_SUSPEND_HINT, &x, 1, NULL, 0);
+
+	/* Enable all EC events while we're awake */
+	olpc_xo175_ec_set_event_mask(EC_ALL_EVENTS);
+
+	return 0;
+}
+
+static struct olpc_ec_driver olpc_xo175_ec_driver = {
+	.ec_cmd = olpc_xo175_ec_cmd,
+};
+
+static int olpc_xo175_ec_remove(struct spi_device *spi)
+{
+	if (pm_power_off == olpc_xo175_ec_power_off)
+		pm_power_off = NULL;
+
+	spi_slave_abort(spi);
+
+	platform_device_unregister(olpc_ec);
+	olpc_ec = NULL;
+
+	return 0;
+}
+
+static int olpc_xo175_ec_probe(struct spi_device *spi)
+{
+	struct olpc_xo175_ec *priv;
+	int ret;
+
+	if (olpc_ec) {
+		dev_err(&spi->dev, "OLPC EC already registered.\n");
+		return -EBUSY;
+	}
+
+	priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->gpio_cmd = devm_gpiod_get(&spi->dev, "cmd", GPIOD_OUT_LOW);
+	if (IS_ERR(priv->gpio_cmd)) {
+		dev_err(&spi->dev, "failed to get cmd gpio: %ld\n",
+					PTR_ERR(priv->gpio_cmd));
+		return PTR_ERR(priv->gpio_cmd);
+	}
+
+	priv->spi = spi;
+
+	spin_lock_init(&priv->cmd_state_lock);
+	priv->cmd_state = CMD_STATE_IDLE;
+	init_completion(&priv->cmd_done);
+
+	priv->logbuf_len = 0;
+
+	/* Set up power button input device */
+	priv->pwrbtn = devm_input_allocate_device(&spi->dev);
+	if (!priv->pwrbtn)
+		return -ENOMEM;
+	priv->pwrbtn->name = "Power Button";
+	priv->pwrbtn->dev.parent = &spi->dev;
+	input_set_capability(priv->pwrbtn, EV_KEY, KEY_POWER);
+	ret = input_register_device(priv->pwrbtn);
+	if (ret) {
+		dev_err(&spi->dev, "error registering input device: %d\n", ret);
+		return ret;
+	}
+
+	spi_set_drvdata(spi, priv);
+
+	priv->xfer.rx_buf = &priv->rx_buf;
+	priv->xfer.tx_buf = &priv->tx_buf;
+
+	olpc_xo175_ec_read_packet(priv);
+
+	olpc_ec_driver_register(&olpc_xo175_ec_driver, priv);
+	olpc_ec = platform_device_register_resndata(&spi->dev, "olpc-ec", -1,
+							NULL, 0, NULL, 0);
+
+	/* Enable all EC events while we're awake */
+	olpc_xo175_ec_set_event_mask(EC_ALL_EVENTS);
+
+	if (pm_power_off == NULL)
+		pm_power_off = olpc_xo175_ec_power_off;
+
+	dev_info(&spi->dev, "OLPC XO-1.75 Embedded Controller driver\n");
+
+	return 0;
+}
+
+static const struct dev_pm_ops olpc_xo175_ec_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, olpc_xo175_ec_resume_noirq)
+	SET_RUNTIME_PM_OPS(olpc_xo175_ec_suspend, olpc_xo175_ec_resume, NULL)
+};
+
+static const struct of_device_id olpc_xo175_ec_of_match[] = {
+	{ .compatible = "olpc,xo1.75-ec" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, olpc_xo175_ec_of_match);
+
+static struct spi_driver olpc_xo175_ec_spi_driver = {
+	.driver = {
+		.name	= "olpc-xo175-ec",
+		.of_match_table = olpc_xo175_ec_of_match,
+		.pm = &olpc_xo175_ec_pm_ops,
+	},
+	.probe		= olpc_xo175_ec_probe,
+	.remove		= olpc_xo175_ec_remove,
+};
+module_spi_driver(olpc_xo175_ec_spi_driver);
+
+MODULE_DESCRIPTION("OLPC XO-1.75 Embedded Controller driver");
+MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>"); /* Functionality */
+MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>"); /* Bugs */
+MODULE_LICENSE("GPL");
diff --git a/include/linux/olpc-ec.h b/include/linux/olpc-ec.h
index f7b6a7eda232..c4602364e909 100644
--- a/include/linux/olpc-ec.h
+++ b/include/linux/olpc-ec.h
@@ -41,7 +41,7 @@ struct olpc_ec_driver {
 	bool wakeup_available;
 };
 
-#ifdef CONFIG_OLPC
+#ifdef CONFIG_OLPC_EC
 
 extern void olpc_ec_driver_register(struct olpc_ec_driver *drv, void *arg);
 
@@ -69,6 +69,6 @@ static inline bool olpc_ec_wakeup_available(void)
 	return false;
 }
 
-#endif /* CONFIG_OLPC */
+#endif /* CONFIG_OLPC_EC */
 
 #endif /* _LINUX_OLPC_EC_H */
-- 
2.21.0

[PATCH v7 07/10] Platform: OLPC: Add a regulator for the DCON

[Lubomir Rintel]

All OLPC ECs are able to turn the power to the DCON on an off. Use the
regulator framework to expose the functionality.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>

---
Changes since v1:
- Use idiomatic form of return on error
- Avoid mixing bool and int

 drivers/platform/olpc/Kconfig   |  1 +
 drivers/platform/olpc/olpc-ec.c | 67 +++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)

diff --git a/drivers/platform/olpc/Kconfig b/drivers/platform/olpc/Kconfig
index 559f843199d7..858ac1d2290a 100644
--- a/drivers/platform/olpc/Kconfig
+++ b/drivers/platform/olpc/Kconfig
@@ -1,4 +1,5 @@
 config OLPC_EC
+	select REGULATOR
 	bool
 
 config OLPC_XO175_EC
diff --git a/drivers/platform/olpc/olpc-ec.c b/drivers/platform/olpc/olpc-ec.c
index a91f78245f5e..8566bcf2938d 100644
--- a/drivers/platform/olpc/olpc-ec.c
+++ b/drivers/platform/olpc/olpc-ec.c
@@ -16,6 +16,7 @@
 #include <linux/workqueue.h>
 #include <linux/init.h>
 #include <linux/list.h>
+#include <linux/regulator/driver.h>
 #include <linux/olpc-ec.h>
 
 struct ec_cmd_desc {
@@ -36,6 +37,10 @@ struct olpc_ec_priv {
 	struct work_struct worker;
 	struct mutex cmd_lock;
 
+	/* DCON regulator */
+	struct regulator_dev *dcon_rdev;
+	bool dcon_enabled;
+
 	/* Pending EC commands */
 	struct list_head cmd_q;
 	spinlock_t cmd_q_lock;
@@ -346,9 +351,61 @@ static struct dentry *olpc_ec_setup_debugfs(void)
 
 #endif /* CONFIG_DEBUG_FS */
 
+static int olpc_ec_set_dcon_power(struct olpc_ec_priv *ec, bool state)
+{
+	unsigned char ec_byte = state;
+	int ret;
+
+	if (ec->dcon_enabled == state)
+		return 0;
+
+	ret = olpc_ec_cmd(EC_DCON_POWER_MODE, &ec_byte, 1, NULL, 0);
+	if (ret)
+		return ret;
+
+	ec->dcon_enabled = state;
+	return 0;
+}
+
+static int dcon_regulator_enable(struct regulator_dev *rdev)
+{
+	struct olpc_ec_priv *ec = rdev_get_drvdata(rdev);
+
+	return olpc_ec_set_dcon_power(ec, true);
+}
+
+static int dcon_regulator_disable(struct regulator_dev *rdev)
+{
+	struct olpc_ec_priv *ec = rdev_get_drvdata(rdev);
+
+	return olpc_ec_set_dcon_power(ec, false);
+}
+
+static int dcon_regulator_is_enabled(struct regulator_dev *rdev)
+{
+	struct olpc_ec_priv *ec = rdev_get_drvdata(rdev);
+
+	return ec->dcon_enabled ? 1 : 0;
+}
+
+static struct regulator_ops dcon_regulator_ops = {
+	.enable		= dcon_regulator_enable,
+	.disable	= dcon_regulator_disable,
+	.is_enabled	= dcon_regulator_is_enabled,
+};
+
+static const struct regulator_desc dcon_desc = {
+	.name	= "dcon",
+	.id	= 0,
+	.ops	= &dcon_regulator_ops,
+	.type	= REGULATOR_VOLTAGE,
+	.owner	= THIS_MODULE,
+};
+
 static int olpc_ec_probe(struct platform_device *pdev)
 {
 	struct olpc_ec_priv *ec;
+	struct regulator_config config = { };
 	int err;
 
 	if (!ec_driver)
@@ -376,6 +433,16 @@ static int olpc_ec_probe(struct platform_device *pdev)
 		return err;
 	}
 
+	config.dev = pdev->dev.parent;
+	config.driver_data = ec;
+	ec->dcon_enabled = true;
+	ec->dcon_rdev = devm_regulator_register(&pdev->dev, &dcon_desc,
+								&config);
+	if (IS_ERR(ec->dcon_rdev)) {
+		dev_err(&pdev->dev, "failed to register DCON regulator\n");
+		return PTR_ERR(ec->dcon_rdev);
+	}
+
 	ec->dbgfs_dir = olpc_ec_setup_debugfs();
 
 	return err;
-- 
2.21.0

[PATCH v7 08/10] power: supply: olpc_battery: Allow building the driver on non-x86

[Lubomir Rintel]

With the recent changes to the driver and addition of OLPC XO-1.75 EC
driver it is possible to use this driver on ARM-based XO laptops as
well.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>

---
 drivers/power/supply/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index e901b9879e7e..66e4d1958de3 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -151,7 +151,7 @@ config BATTERY_PMU
 
 config BATTERY_OLPC
 	tristate "One Laptop Per Child battery"
-	depends on X86_32 && OLPC
+	depends on OLPC_EC
 	help
 	  Say Y to enable support for the battery on the OLPC laptop.
 
-- 
2.21.0

[PATCH v7 09/10] ARM: export arm_pm_restart

[Lubomir Rintel]

The OLPC XO 1.75 laptop is rebooted with a command to the Embedded
Controller. The EC driver should be a module, since most people don't need
it to be compiled in.

The EC driver can't use register_restart_handler() because handlers
registered with it are executed in atomic context and the XO 1.75 reboot
dance needs to block: the reboot is initiated by poking a GPIO ofter
which we need to wait for the EC to initiate a SPI transfer and finish
it.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>

---
Changes since v4:
- Clarify why we need this

 arch/arm/kernel/reboot.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/kernel/reboot.c b/arch/arm/kernel/reboot.c
index 3b2aa9a9fe26..71016cf19b86 100644
--- a/arch/arm/kernel/reboot.c
+++ b/arch/arm/kernel/reboot.c
@@ -22,6 +22,7 @@ typedef void (*phys_reset_t)(unsigned long, bool);
  * Function pointers to optional machine specific functions
  */
 void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
+EXPORT_SYMBOL_GPL(arm_pm_restart);
 void (*pm_power_off)(void);
 EXPORT_SYMBOL(pm_power_off);
 
-- 
2.21.0

[PATCH v7 10/10] Platform: OLPC: Add restart support to XO-1.75 EC driver

[Lubomir Rintel]

This hooks to arm_pm_restart instead od utilizing a restart handler
notifier, because the reboot dance on XO 1.75 needs to sleep (it pokes a
GPIO and waits for the EC to initiate the command transaction) and the
restart handler is called in atomic context. Sad.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>

---
Changes since v4:
- Split off from the driver.

 drivers/platform/olpc/Kconfig         |  2 +-
 drivers/platform/olpc/olpc-xo175-ec.c | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/olpc/Kconfig b/drivers/platform/olpc/Kconfig
index 858ac1d2290a..02b232c34444 100644
--- a/drivers/platform/olpc/Kconfig
+++ b/drivers/platform/olpc/Kconfig
@@ -4,7 +4,7 @@ config OLPC_EC
 
 config OLPC_XO175_EC
 	tristate "OLPC XO 1.75 Embedded Controller"
-	depends on ARCH_MMP || COMPILE_TEST
+	depends on ARM && (ARCH_MMP || COMPILE_TEST)
 	select SPI_SLAVE
 	select OLPC_EC
 	help
diff --git a/drivers/platform/olpc/olpc-xo175-ec.c b/drivers/platform/olpc/olpc-xo175-ec.c
index 344d14f3da54..b64443605a03 100644
--- a/drivers/platform/olpc/olpc-xo175-ec.c
+++ b/drivers/platform/olpc/olpc-xo175-ec.c
@@ -23,6 +23,7 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/spi/spi.h>
+#include <asm/system_misc.h>
 
 struct ec_cmd_t {
 	u8 cmd;
@@ -580,6 +581,14 @@ static int olpc_xo175_ec_set_event_mask(unsigned int mask)
 	return olpc_ec_cmd(CMD_WRITE_EXT_SCI_MASK, args, 2, NULL, 0);
 }
 
+static void olpc_xo175_ec_restart(enum reboot_mode mode, const char *cmd)
+{
+	while (1) {
+		olpc_ec_cmd(CMD_POWER_CYCLE, NULL, 0, NULL, 0);
+		mdelay(1000);
+	}
+}
+
 static void olpc_xo175_ec_power_off(void)
 {
 	while (1) {
@@ -651,6 +660,8 @@ static int olpc_xo175_ec_remove(struct spi_device *spi)
 {
 	if (pm_power_off == olpc_xo175_ec_power_off)
 		pm_power_off = NULL;
+	if (arm_pm_restart == olpc_xo175_ec_restart)
+		arm_pm_restart = NULL;
 
 	spi_slave_abort(spi);
 
@@ -718,6 +729,8 @@ static int olpc_xo175_ec_probe(struct spi_device *spi)
 
 	if (pm_power_off == NULL)
 		pm_power_off = olpc_xo175_ec_power_off;
+	if (arm_pm_restart == NULL)
+		arm_pm_restart = olpc_xo175_ec_restart;
 
 	dev_info(&spi->dev, "OLPC XO-1.75 Embedded Controller driver\n");
 
-- 
2.21.0

Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Pavel Machek]

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On Mon 2019-05-13 09:56:32, Lubomir Rintel wrote:
> The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
> signals for handshaking. It needs to know when is the slave (Linux)
> side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
> controller node) and when does it wish to respond with a command (the
> cmd-gpio property).
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> Acked-by: Pavel Machek <pavel@ucw.cz>
> Reviewed-by: Rob Herring <robh@kernel.org>

Who is expected to apply this? I don't think more iterations will make
it better... it seems pretty good already :-).

								Pavel
								
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Lubomir Rintel]

On Mon, 2019-05-13 at 11:07 +0200, Pavel Machek wrote:
> On Mon 2019-05-13 09:56:32, Lubomir Rintel wrote:
> > The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
> > signals for handshaking. It needs to know when is the slave (Linux)
> > side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
> > controller node) and when does it wish to respond with a command (the
> > cmd-gpio property).
> > 
> > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> > Acked-by: Pavel Machek <pavel@ucw.cz>
> > Reviewed-by: Rob Herring <robh@kernel.org>
> 
> Who is expected to apply this? I don't think more iterations will make
> it better... it seems pretty good already :-).

The whole set is meant to go in through platform/x86; it just missed
5.2 due to some issues discovered by the kbuild bot when it entered
Andy's review queue.

> 
> 								Pavel
> 								

Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Andy Shevchenko]

On Mon, May 13, 2019 at 4:18 PM Lubomir Rintel <lkundrak@v3.sk> wrote:
>
> On Mon, 2019-05-13 at 11:07 +0200, Pavel Machek wrote:
> > On Mon 2019-05-13 09:56:32, Lubomir Rintel wrote:
> > > The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra
> > > signals for handshaking. It needs to know when is the slave (Linux)
> > > side's TX FIFO ready for transfer (the ready-gpio signal on the SPI
> > > controller node) and when does it wish to respond with a command (the
> > > cmd-gpio property).
> > >
> > > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> > > Acked-by: Pavel Machek <pavel@ucw.cz>
> > > Reviewed-by: Rob Herring <robh@kernel.org>
> >
> > Who is expected to apply this? I don't think more iterations will make
> > it better... it seems pretty good already :-).
>
> The whole set is meant to go in through platform/x86; it just missed
> 5.2 due to some issues discovered by the kbuild bot when it entered
> Andy's review queue.

It will be promoted in a few days to our for-next.

-- 
With Best Regards,
Andy Shevchenko

OLPC in 5.3? was Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Pavel Machek]

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Hi!

What is status of OLPC-1.75 in v5.3? IIRC most of the patches went in,
but I don't see suitable dts file in the tree. I tried porting one
from working (4.19 or so) kernel, but it was not quite trivial.

Is there time for dts to be merged?

Thanks,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: OLPC in 5.3? was Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Lubomir Rintel]

Hello Pavel,

On Thu, 2019-08-01 at 21:27 +0200, Pavel Machek wrote:
> Hi!
> 
> What is status of OLPC-1.75 in v5.3? IIRC most of the patches went in,
> but I don't see suitable dts file in the tree. I tried porting one
> from working (4.19 or so) kernel, but it was not quite trivial.
> 
> Is there time for dts to be merged?

Short answer is that it's not absolutely necessary. With a new enough
OpenFirmware, the firmware will just construct a correct FDT.

To upgrade your machine to the new firmware, just copy 
http://dev.laptop.org/~quozl/q4e00ja.rom to a FAT partition on a USB
flash stick and run "flash u:\q4e00ja.rom" from the "ok" prompt.
Then you'll be able to run stock mainline kernels happily.

That said, it might still be useful to have a DTS file in tree (for
reference, testing, machines with older firmware, etc.). I've now re-
sent the MMP2 devicetree update patch set with the DTS file included
and copied you on that one.

As usual, I'm thankful for testing, reviews and acks.

Take care!

Lubo

Re: OLPC in 5.3? was Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Pavel Machek]

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Hi!

> > What is status of OLPC-1.75 in v5.3? IIRC most of the patches went in,
> > but I don't see suitable dts file in the tree. I tried porting one
> > from working (4.19 or so) kernel, but it was not quite trivial.
> > 
> > Is there time for dts to be merged?
> 
> Short answer is that it's not absolutely necessary. With a new enough
> OpenFirmware, the firmware will just construct a correct FDT.

> To upgrade your machine to the new firmware, just copy 
> http://dev.laptop.org/~quozl/q4e00ja.rom to a FAT partition on a USB
> flash stick and run "flash u:\q4e00ja.rom" from the "ok" prompt.
> Then you'll be able to run stock mainline kernels happily.

Aha, good, thanks. That went smoothly.

> That said, it might still be useful to have a DTS file in tree (for
> reference, testing, machines with older firmware, etc.). I've now re-
> sent the MMP2 devicetree update patch set with the DTS file included
> and copied you on that one.

Yes: sometimes it is neccessary to modify the dts. I was changing the
kernel command line, for example.

> As usual, I'm thankful for testing, reviews and acks.

I'll take a look. I tried 5.2 with defconfig from one of the branches
(olpc_xo175_defconfig), and that does not boot.

What config should I use? Is it enough to produce zImage and put it on
the flashdisk with olpc.fth file? Is there some kind of documentation
somewhere? :-).

Thanks and best regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: OLPC in 5.3? was Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Lubomir Rintel]

----- On Aug 3, 2019, at 10:47 AM, Pavel Machek pavel@ucw.cz wrote:

> Hi!
> 
>> > What is status of OLPC-1.75 in v5.3? IIRC most of the patches went in,
>> > but I don't see suitable dts file in the tree. I tried porting one
>> > from working (4.19 or so) kernel, but it was not quite trivial.
>> > 
>> > Is there time for dts to be merged?
>> 
>> Short answer is that it's not absolutely necessary. With a new enough
>> OpenFirmware, the firmware will just construct a correct FDT.
> 
>> To upgrade your machine to the new firmware, just copy
>> http://dev.laptop.org/~quozl/q4e00ja.rom to a FAT partition on a USB
>> flash stick and run "flash u:\q4e00ja.rom" from the "ok" prompt.
>> Then you'll be able to run stock mainline kernels happily.
> 
> Aha, good, thanks. That went smoothly.
> 
>> That said, it might still be useful to have a DTS file in tree (for
>> reference, testing, machines with older firmware, etc.). I've now re-
>> sent the MMP2 devicetree update patch set with the DTS file included
>> and copied you on that one.
> 
> Yes: sometimes it is neccessary to modify the dts. I was changing the
> kernel command line, for example.

Well, you can do that from OFW too. E.g.:

  " console=ttyS2,115200" to boot-file

>> As usual, I'm thankful for testing, reviews and acks.
> 
> I'll take a look. I tried 5.2 with defconfig from one of the branches
> (olpc_xo175_defconfig), and that does not boot.

I'm using [1].

[1] https://raw.githubusercontent.com/hackerspace/olpc-xo175-linux/lr/olpc-xo175/arch/arm/configs/olpc_xo175_defconfig

I'm wondering if it would make sense to include this upstream?
My guess was that nowadays multi_v7_defconfig that just works
on any DT-based platform is preferred to machine specific ones.

However, this one would enable OLPC-specific drivers the
multi_v7_defconfig defconfig wouldn't.

I've sent out an update to multi_v7_defconfig [2]. Once it is applied,
it should work on the XO-1.75 (without fancy things like camera or
power button).

[2] https://lore.kernel.org/lkml/20190620114816.1387881-1-lkundrak@v3.sk/

> What config should I use? Is it enough to produce zImage and put it on
> the flashdisk with olpc.fth file?

Yes. OFW loads olpc.fth from the first active FAT or ext3 partition on
SD card or a USB flash drive. If you put the zImage in the same place,
the following script would work:
  
  \ OLPC boot script

  " last:\zImage" to boot-device
  visible unfreeze
  boot

Note that it has to start with a backslash. The "visible" and "unfreeze"
words enable the DCON pass-through mode. You would see the XO logo
instead of the actual screen output without it.

> Is there some kind of documentation somewhere? :-).

This is always a tough question. Short answer would be no.

I'm happy to answer questions though, if the above wouldn't be
sufficient to make the thing boot for you.

I'd prefer if things just worked to documenting how to hack things
to make them work. If you got a Fedora machine, you can already
just pick a nightly [1] armhfp image and install it with
fedora-arm-installer the same way as any other ARM machine. I hope
to make Debian work too. An image that already boots would then
hopefully be a good start for whoever wishes to run their own kernels.
That's my excuse for not documenting things...

[1] https://www.happyassassin.net/nightlies.html

> Thanks and best regards,
> Pavel

Take care
Lubo

> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures)
> http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: OLPC in 5.3? was Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Pavel Machek]

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Hi!

> I'm using [1].
> 
> [1] https://raw.githubusercontent.com/hackerspace/olpc-xo175-linux/lr/olpc-xo175/arch/arm/configs/olpc_xo175_defconfig
> 

Thanks a lot. I got it to work with 5.2 and 5.3-rc. One thing I
noticed...

"reboot: Restarting system", "Reboot failed --- System halted".

> I'm wondering if it would make sense to include this upstream?
> My guess was that nowadays multi_v7_defconfig that just works
> on any DT-based platform is preferred to machine specific ones.
> 
> However, this one would enable OLPC-specific drivers the
> multi_v7_defconfig defconfig wouldn't.

Yes, I believe that would be useful. Getting all the extras without
that would be quite tricky. 

> > Is there some kind of documentation somewhere? :-).
> 
> This is always a tough question. Short answer would be no.
> 
> I'm happy to answer questions though, if the above wouldn't be
> sufficient to make the thing boot for you.

Ok, it seems to work now ;-). I'll make some notes...

Best regards,

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: OLPC in 5.3? was Re: [PATCH v7 01/10] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings

[Lubomir Rintel]

On Wed, 2019-08-07 at 14:31 +0200, Pavel Machek wrote:
> Hi!
> 
> > I'm using [1].
> > 
> > [1] https://raw.githubusercontent.com/hackerspace/olpc-xo175-linux/lr/olpc-xo175/arch/arm/configs/olpc_xo175_defconfig
> > 
> 
> Thanks a lot. I got it to work with 5.2 and 5.3-rc. One thing I
> noticed...
> 
> "reboot: Restarting system", "Reboot failed --- System halted".

Yes. Another unhappy Russel issue, if it's fair to put it that way. :)
Ideas appreciated.

https://lore.kernel.org/lkml/20190108233137.GW11171@n2100.armlinux.org.uk/

> 
> > I'm wondering if it would make sense to include this upstream?
> > My guess was that nowadays multi_v7_defconfig that just works
> > on any DT-based platform is preferred to machine specific ones.
> > 
> > However, this one would enable OLPC-specific drivers the
> > multi_v7_defconfig defconfig wouldn't.
> 
> Yes, I believe that would be useful. Getting all the extras without
> that would be quite tricky.

Okay, I'll take a mental note to send it out eventually.

> > > Is there some kind of documentation somewhere? :-).
> > 
> > This is always a tough question. Short answer would be no.
> > 
> > I'm happy to answer questions though, if the above wouldn't be
> > sufficient to make the thing boot for you.
> 
> Ok, it seems to work now ;-). I'll make some notes...

That's cool.

> 
> Best regards,
> 
> 									Pavel

Take care
Lubo