Commit 1f866057 authored by Stefan Berger's avatar Stefan Berger Committed by Kent Yoder
Browse files

tpm: Fix cancellation of TPM commands (polling mode) 



On one of my machines the cancellation of TPM commands does not work.
The reason is that by writing into sysfs 'cancel' the tpm_tis_ready
call causes the status flag TPM_STS_VALID to be set in the statusregister.
However, the TIS driver seems to wait for TPM_STS_COMMAND_READY.
Once a 2nd time sysfs 'cancel' is written to, the TPM_STS_COMMAND_READY flag
also gets set, resulting in TPM_STS_VALID|TPM_STS_COMMAND_READY to be
read from the status register.

This patch now converts req_canceled into a function to enable more complex
comparisons against possible cancellation status codes.

Signed-off-by: default avatarStefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: default avatarKent Yoder <key@linux.vnet.ibm.com>
parent 3e3a5e90

drivers/char/tpm/tpm.c

+1 −1
Original line number Diff line number Diff line
@@ -393,7 +393,7 @@ static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf, 
		    chip->vendor.req_complete_val)

			goto out_recv;



		if ((status == chip->vendor.req_canceled)) {

		if (chip->vendor.req_canceled(chip, status)) {

			dev_err(chip->dev, "Operation Canceled\n");

			rc = -ECANCELED;

			goto out;

drivers/char/tpm/tpm.h

+3 −1
Original line number Diff line number Diff line
@@ -78,7 +78,7 @@ struct tpm_chip; 
struct tpm_vendor_specific {

	const u8 req_complete_mask;

	const u8 req_complete_val;

	const u8 req_canceled;

	bool (*req_canceled)(struct tpm_chip *chip, u8 status);

	void __iomem *iobase;		/* ioremapped address */

	unsigned long base;		/* TPM base address */
@@ -112,6 +112,8 @@ struct tpm_vendor_specific { 
#define TPM_VPRIV(c)	(c)->vendor.priv



#define TPM_VID_INTEL    0x8086

#define TPM_VID_WINBOND  0x1050

#define TPM_VID_STM      0x104A



struct tpm_chip {

	struct device *dev;	/* Device stuff */

drivers/char/tpm/tpm_atmel.c

+6 −1
Original line number Diff line number Diff line
@@ -116,6 +116,11 @@ static u8 tpm_atml_status(struct tpm_chip *chip) 
	return ioread8(chip->vendor.iobase + 1);

}



static bool tpm_atml_req_canceled(struct tpm_chip *chip, u8 status)

{

	return (status == ATML_STATUS_READY);

}



static const struct file_operations atmel_ops = {

	.owner = THIS_MODULE,

	.llseek = no_llseek,
@@ -147,7 +152,7 @@ static const struct tpm_vendor_specific tpm_atmel = { 
	.status = tpm_atml_status,

	.req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,

	.req_complete_val = ATML_STATUS_DATA_AVAIL,

	.req_canceled = ATML_STATUS_READY,

	.req_canceled = tpm_atml_req_canceled,

	.attr_group = &atmel_attr_grp,

	.miscdev = { .fops = &atmel_ops, },

};

drivers/char/tpm/tpm_i2c_infineon.c

+6 −1
Original line number Diff line number Diff line
@@ -505,6 +505,11 @@ out_err: 
	return rc;

}



static bool tpm_tis_i2c_req_canceled(struct tpm_chip *chip, u8 status)

{

	return (status == TPM_STS_COMMAND_READY);

}



static const struct file_operations tis_ops = {

	.owner = THIS_MODULE,

	.llseek = no_llseek,
@@ -550,7 +555,7 @@ static struct tpm_vendor_specific tpm_tis_i2c = { 
	.cancel = tpm_tis_i2c_ready,

	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,

	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,

	.req_canceled = TPM_STS_COMMAND_READY,

	.req_canceled = tpm_tis_i2c_req_canceled,

	.attr_group = &tis_attr_grp,

	.miscdev.fops = &tis_ops,

};

drivers/char/tpm/tpm_i2c_stm_st33.c

+6 −1
Original line number Diff line number Diff line
@@ -587,6 +587,11 @@ out: 
	return size;

}



static bool tpm_st33_i2c_req_canceled(struct tpm_chip *chip, u8 status)

{

       return (status == TPM_STS_COMMAND_READY);

}



static const struct file_operations tpm_st33_i2c_fops = {

	.owner = THIS_MODULE,

	.llseek = no_llseek,
@@ -627,7 +632,7 @@ static struct tpm_vendor_specific st_i2c_tpm = { 
	.status = tpm_stm_i2c_status,

	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,

	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,

	.req_canceled = TPM_STS_COMMAND_READY,

	.req_canceled = tpm_st33_i2c_req_canceled,

	.attr_group = &stm_tpm_attr_grp,

	.miscdev = {.fops = &tpm_st33_i2c_fops,},

};

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