Merge branch 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:
 "For 3.19, the I2C subsystem has to offer special candy this time.
  Right in time for Christmas :)

   - I2C slave framework: finally, a generic mechanism for Linux being
     an I2C slave (if the bus driver supports that).  Docs are still
     missing but will come later this cycle, the code is good enough to
     go.
   - I2C muxes represent their topology in sysfs much more detailed.
     This will help users to navigate around much easier.
   - irq population of i2c clients is now done at probe time, not device
     creation time, to have better support for deferred probing.
   - new drivers for Imagination SCB, Amlogic Meson
   - DMA support added for Freescale IMX, Renesas SHMobile
   - slightly bigger driver updates to OMAP, i801, AT91, and rk3x
     (mostly quirk handling, timing updates, and using better kernel
     interfaces)
   - eeprom driver can now write with byte-access (very slow, but OK to
     have)
   - and the bunch of smaller fixes, cleanups, ID updates..."

* 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (56 commits)
  i2c: sh_mobile: remove unneeded DMA mask
  i2c: rcar: add slave support
  i2c: slave-eeprom: add eeprom simulator driver
  i2c: core changes for slave support
  MAINTAINERS: add I2C dt bindings also to I2C realm
  i2c: designware: Fix falling time bindings doc
  i2c: davinci: switch to use platform_get_irq
  Documentation: i2c: Use PM ops instead of legacy suspend/resume
  i2c: sh_mobile: optimize irq entry
  i2c: pxa: add support for SCCB devices
  omap: i2c: don't check bus state IP rev3.3 and earlier
  i2c: s3c2410: Handle i2c sys_cfg register in i2c driver
  i2c: rk3x: add Kconfig dependency on COMMON_CLK
  i2c: omap: add notes related to i2c multimaster mode
  i2c: omap: don't reset controller if Arbitration Lost detected
  i2c: omap: implement workaround for handling invalid BB-bit values
  i2c: omap: cleanup register definitions
  i2c: rk3x: handle dynamic clock rate changes correctly
  i2c: at91: enable probe deferring on dma channel request
  i2c: at91: remove legacy DMA support
  ...

1 files changed, 48 insertions, 9 deletions

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 6ab4f1cb21f3..8fafb254e42a 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -2,7 +2,7 @@
     Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
     Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker
     <mdsxyz123@yahoo.com>
-    Copyright (C) 2007 - 2012  Jean Delvare <jdelvare@suse.de>
+    Copyright (C) 2007 - 2014  Jean Delvare <jdelvare@suse.de>
     Copyright (C) 2010         Intel Corporation,
                                David Woodhouse <dwmw2@infradead.org>
 
@@ -59,6 +59,7 @@
  * Wildcat Point-LP (PCH)	0x9ca2	32	hard	yes	yes	yes
  * BayTrail (SOC)		0x0f12	32	hard	yes	yes	yes
  * Sunrise Point-H (PCH) 	0xa123  32	hard	yes	yes	yes
+ * Sunrise Point-LP (PCH)	0x9d23	32	hard	yes	yes	yes
  *
  * Features supported by this driver:
  * Software PEC				no
@@ -109,12 +110,16 @@
 
 /* PCI Address Constants */
 #define SMBBAR		4
+#define SMBPCICTL	0x004
 #define SMBPCISTS	0x006
 #define SMBHSTCFG	0x040
 
 /* Host status bits for SMBPCISTS */
 #define SMBPCISTS_INTS		0x08
 
+/* Control bits for SMBPCICTL */
+#define SMBPCICTL_INTDIS	0x0400
+
 /* Host configuration bits for SMBHSTCFG */
 #define SMBHSTCFG_HST_EN	1
 #define SMBHSTCFG_SMB_SMI_EN	2
@@ -182,6 +187,7 @@
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS		0x9c22
 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS	0x9ca2
 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS	0xa123
+#define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS	0x9d23
 
 struct i801_mux_config {
 	char *gpio_chip;
@@ -371,6 +377,7 @@ static int i801_transaction(struct i801_priv *priv, int xact)
 {
 	int status;
 	int result;
+	const struct i2c_adapter *adap = &priv->adapter;
 
 	result = i801_check_pre(priv);
 	if (result < 0)
@@ -379,7 +386,14 @@ static int i801_transaction(struct i801_priv *priv, int xact)
 	if (priv->features & FEATURE_IRQ) {
 		outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,
 		       SMBHSTCNT(priv));
-		wait_event(priv->waitq, (status = priv->status));
+		result = wait_event_timeout(priv->waitq,
+					    (status = priv->status),
+					    adap->timeout);
+		if (!result) {
+			status = -ETIMEDOUT;
+			dev_warn(&priv->pci_dev->dev,
+				 "Timeout waiting for interrupt!\n");
+		}
 		priv->status = 0;
 		return i801_check_post(priv, status);
 	}
@@ -493,9 +507,6 @@ static irqreturn_t i801_isr(int irq, void *dev_id)
 		return IRQ_NONE;
 
 	status = inb_p(SMBHSTSTS(priv));
-	if (status != 0x42)
-		dev_dbg(&priv->pci_dev->dev, "irq: status = %02x\n", status);
-
 	if (status & SMBHSTSTS_BYTE_DONE)
 		i801_isr_byte_done(priv);
 
@@ -527,6 +538,7 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
 	int smbcmd;
 	int status;
 	int result;
+	const struct i2c_adapter *adap = &priv->adapter;
 
 	result = i801_check_pre(priv);
 	if (result < 0)
@@ -555,7 +567,14 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
 		priv->data = &data->block[1];
 
 		outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));
-		wait_event(priv->waitq, (status = priv->status));
+		result = wait_event_timeout(priv->waitq,
+					    (status = priv->status),
+					    adap->timeout);
+		if (!result) {
+			status = -ETIMEDOUT;
+			dev_warn(&priv->pci_dev->dev,
+				 "Timeout waiting for interrupt!\n");
+		}
 		priv->status = 0;
 		return i801_check_post(priv, status);
 	}
@@ -829,6 +848,7 @@ static const struct pci_device_id i801_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS) },
 	{ 0, }
 };
 
@@ -1212,6 +1232,25 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 		outb_p(inb_p(SMBAUXCTL(priv)) &
 		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));
 
+	/* Default timeout in interrupt mode: 200 ms */
+	priv->adapter.timeout = HZ / 5;
+
+	if (priv->features & FEATURE_IRQ) {
+		u16 pcictl, pcists;
+
+		/* Complain if an interrupt is already pending */
+		pci_read_config_word(priv->pci_dev, SMBPCISTS, &pcists);
+		if (pcists & SMBPCISTS_INTS)
+			dev_warn(&dev->dev, "An interrupt is pending!\n");
+
+		/* Check if interrupts have been disabled */
+		pci_read_config_word(priv->pci_dev, SMBPCICTL, &pcictl);
+		if (pcictl & SMBPCICTL_INTDIS) {
+			dev_info(&dev->dev, "Interrupts are disabled\n");
+			priv->features &= ~FEATURE_IRQ;
+		}
+	}
+
 	if (priv->features & FEATURE_IRQ) {
 		init_waitqueue_head(&priv->waitq);
 
@@ -1220,10 +1259,11 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 		if (err) {
 			dev_err(&dev->dev, "Failed to allocate irq %d: %d\n",
 				dev->irq, err);
-			goto exit_release;
+			priv->features &= ~FEATURE_IRQ;
 		}
-		dev_info(&dev->dev, "SMBus using PCI Interrupt\n");
 	}
+	dev_info(&dev->dev, "SMBus using %s\n",
+		 priv->features & FEATURE_IRQ ? "PCI interrupt" : "polling");
 
 	/* set up the sysfs linkage to our parent device */
 	priv->adapter.dev.parent = &dev->dev;
@@ -1250,7 +1290,6 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 exit_free_irq:
 	if (priv->features & FEATURE_IRQ)
 		free_irq(dev->irq, priv);
-exit_release:
 	pci_release_region(dev, SMBBAR);
 exit:
 	kfree(priv);