Commit 80d75202 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

Pull i2c fixes from Wolfram Sang:
 "I2C has an interrupt storm fix for the i801, better timeout handling
  for the new virtio driver, and some documentation fixes this time"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  docs: i2c: smbus-protocol: mention the repeated start condition
  i2c: virtio: disable timeout handling
  i2c: i801: Fix interrupt storm from SMB_ALERT signal
  i2c: i801: Restore INTREN on unload
  dt-bindings: i2c: imx-lpi2c: Fix i.MX 8QM compatible matching
parents 6b54698a bed68f4f

Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.yaml

+3 −2
Original line number Diff line number Diff line
@@ -17,9 +17,10 @@ properties: 
    oneOf:

      - enum:

          - fsl,imx7ulp-lpi2c

          - fsl,imx8qm-lpi2c

      - items:

          - const: fsl,imx8qxp-lpi2c

          - enum:

              - fsl,imx8qxp-lpi2c

              - fsl,imx8qm-lpi2c

          - const: fsl,imx7ulp-lpi2c



  reg:

Documentation/i2c/smbus-protocol.rst

+8 −6
Original line number Diff line number Diff line
@@ -36,6 +36,8 @@ Key to symbols 


=============== =============================================================

S               Start condition

Sr              Repeated start condition, used to switch from write to

                read mode.

P               Stop condition

Rd/Wr (1 bit)   Read/Write bit. Rd equals 1, Wr equals 0.

A, NA (1 bit)   Acknowledge (ACK) and Not Acknowledge (NACK) bit
@@ -100,7 +102,7 @@ Implemented by i2c_smbus_read_byte_data() 
This reads a single byte from a device, from a designated register.

The register is specified through the Comm byte::



  S Addr Wr [A] Comm [A] S Addr Rd [A] [Data] NA P

  S Addr Wr [A] Comm [A] Sr Addr Rd [A] [Data] NA P



Functionality flag: I2C_FUNC_SMBUS_READ_BYTE_DATA
@@ -114,7 +116,7 @@ This operation is very like Read Byte; again, data is read from a 
device, from a designated register that is specified through the Comm

byte. But this time, the data is a complete word (16 bits)::



  S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P

  S Addr Wr [A] Comm [A] Sr Addr Rd [A] [DataLow] A [DataHigh] NA P



Functionality flag: I2C_FUNC_SMBUS_READ_WORD_DATA
@@ -164,7 +166,7 @@ This command selects a device register (through the Comm byte), sends 
16 bits of data to it, and reads 16 bits of data in return::



  S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A]

                               S Addr Rd [A] [DataLow] A [DataHigh] NA P

                              Sr Addr Rd [A] [DataLow] A [DataHigh] NA P



Functionality flag: I2C_FUNC_SMBUS_PROC_CALL
@@ -181,7 +183,7 @@ of data is specified by the device in the Count byte. 
::



  S Addr Wr [A] Comm [A]

             S Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P

            Sr Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P



Functionality flag: I2C_FUNC_SMBUS_READ_BLOCK_DATA
@@ -212,7 +214,7 @@ This command selects a device register (through the Comm byte), sends 
1 to 31 bytes of data to it, and reads 1 to 31 bytes of data in return::



  S Addr Wr [A] Comm [A] Count [A] Data [A] ...

                               S Addr Rd [A] [Count] A [Data] ... A P

                              Sr Addr Rd [A] [Count] A [Data] ... A P



Functionality flag: I2C_FUNC_SMBUS_BLOCK_PROC_CALL
@@ -300,7 +302,7 @@ This command reads a block of bytes from a device, from a 
designated register that is specified through the Comm byte::



  S Addr Wr [A] Comm [A]

             S Addr Rd [A] [Data] A [Data] A ... A [Data] NA P

            Sr Addr Rd [A] [Data] A [Data] A ... A [Data] NA P



Functionality flag: I2C_FUNC_SMBUS_READ_I2C_BLOCK

drivers/i2c/busses/i2c-i801.c

+25 −7
Original line number Diff line number Diff line
@@ -191,6 +191,7 @@ 
#define SMBSLVSTS_HST_NTFY_STS	BIT(0)



/* Host Notify Command register bits */

#define SMBSLVCMD_SMBALERT_DISABLE	BIT(2)

#define SMBSLVCMD_HST_NTFY_INTREN	BIT(0)



#define STATUS_ERROR_FLAGS	(SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \
@@ -259,6 +260,7 @@ struct i801_priv { 
	struct i2c_adapter adapter;

	unsigned long smba;

	unsigned char original_hstcfg;

	unsigned char original_hstcnt;

	unsigned char original_slvcmd;

	struct pci_dev *pci_dev;

	unsigned int features;
@@ -641,12 +643,20 @@ static irqreturn_t i801_isr(int irq, void *dev_id) 
		i801_isr_byte_done(priv);



	/*

	 * Clear irq sources and report transaction result.

	 * Clear remaining IRQ sources: Completion of last command, errors

	 * and the SMB_ALERT signal. SMB_ALERT status is set after signal

	 * assertion independently of the interrupt generation being blocked

	 * or not so clear it always when the status is set.

	 */

	status &= SMBHSTSTS_INTR | STATUS_ERROR_FLAGS | SMBHSTSTS_SMBALERT_STS;

	if (status)

		outb_p(status, SMBHSTSTS(priv));

	status &= ~SMBHSTSTS_SMBALERT_STS; /* SMB_ALERT not reported */

	/*

	 * Report transaction result.

	 * ->status must be cleared before the next transaction is started.

	 */

	status &= SMBHSTSTS_INTR | STATUS_ERROR_FLAGS;

	if (status) {

		outb_p(status, SMBHSTSTS(priv));

		priv->status = status;

		complete(&priv->done);

	}
@@ -974,9 +984,13 @@ static void i801_enable_host_notify(struct i2c_adapter *adapter) 
	if (!(priv->features & FEATURE_HOST_NOTIFY))

		return;



	if (!(SMBSLVCMD_HST_NTFY_INTREN & priv->original_slvcmd))

		outb_p(SMBSLVCMD_HST_NTFY_INTREN | priv->original_slvcmd,

		       SMBSLVCMD(priv));

	/*

	 * Enable host notify interrupt and block the generation of interrupt

	 * from the SMB_ALERT signal because the driver does not support

	 * SMBus Alert.

	 */

	outb_p(SMBSLVCMD_HST_NTFY_INTREN | SMBSLVCMD_SMBALERT_DISABLE |

	       priv->original_slvcmd, SMBSLVCMD(priv));



	/* clear Host Notify bit to allow a new notification */

	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
@@ -1805,7 +1819,8 @@ 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));



	/* Remember original Host Notify setting */

	/* Remember original Interrupt and Host Notify settings */

	priv->original_hstcnt = inb_p(SMBHSTCNT(priv)) & ~SMBHSTCNT_KILL;

	if (priv->features & FEATURE_HOST_NOTIFY)

		priv->original_slvcmd = inb_p(SMBSLVCMD(priv));
@@ -1869,6 +1884,7 @@ static void i801_remove(struct pci_dev *dev) 
{

	struct i801_priv *priv = pci_get_drvdata(dev);



	outb_p(priv->original_hstcnt, SMBHSTCNT(priv));

	i801_disable_host_notify(priv);

	i801_del_mux(priv);

	i2c_del_adapter(&priv->adapter);
@@ -1892,6 +1908,7 @@ static void i801_shutdown(struct pci_dev *dev) 
	struct i801_priv *priv = pci_get_drvdata(dev);



	/* Restore config registers to avoid hard hang on some systems */

	outb_p(priv->original_hstcnt, SMBHSTCNT(priv));

	i801_disable_host_notify(priv);

	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);

}
@@ -1901,6 +1918,7 @@ static int i801_suspend(struct device *dev) 
{

	struct i801_priv *priv = dev_get_drvdata(dev);



	outb_p(priv->original_hstcnt, SMBHSTCNT(priv));

	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, priv->original_hstcfg);

	return 0;

}

drivers/i2c/busses/i2c-virtio.c

+5 −9
Original line number Diff line number Diff line
@@ -104,11 +104,10 @@ static int virtio_i2c_prepare_reqs(struct virtqueue *vq, 


static int virtio_i2c_complete_reqs(struct virtqueue *vq,

				    struct virtio_i2c_req *reqs,

				    struct i2c_msg *msgs, int num,

				    bool timedout)

				    struct i2c_msg *msgs, int num)

{

	struct virtio_i2c_req *req;

	bool failed = timedout;

	bool failed = false;

	unsigned int len;

	int i, j = 0;
@@ -130,7 +129,7 @@ static int virtio_i2c_complete_reqs(struct virtqueue *vq, 
			j++;

	}



	return timedout ? -ETIMEDOUT : j;

	return j;

}



static int virtio_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
@@ -139,7 +138,6 @@ static int virtio_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, 
	struct virtio_i2c *vi = i2c_get_adapdata(adap);

	struct virtqueue *vq = vi->vq;

	struct virtio_i2c_req *reqs;

	unsigned long time_left;

	int count;



	reqs = kcalloc(num, sizeof(*reqs), GFP_KERNEL);
@@ -162,11 +160,9 @@ static int virtio_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, 
	reinit_completion(&vi->completion);

	virtqueue_kick(vq);



	time_left = wait_for_completion_timeout(&vi->completion, adap->timeout);

	if (!time_left)

		dev_err(&adap->dev, "virtio i2c backend timeout.\n");

	wait_for_completion(&vi->completion);



	count = virtio_i2c_complete_reqs(vq, reqs, msgs, count, !time_left);

	count = virtio_i2c_complete_reqs(vq, reqs, msgs, count);



err_free:

	kfree(reqs);