tpm_crb: Clean-up and refactor check for idle support

Refactor TPM idle check to tpm_crb_has_idle(), and reduce paraentheses
usage in start method checks

[jarkko: Fine-tuned the commit message.]

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Stuart Yoder <stuart.yoder@arm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>

Author: stuyod01

drivers/char/tpm/tpm_crb.c

@@ -115,6 +115,16 @@ struct tpm2_crb_pluton {
 	u64 reply_addr;
 };
 
+/*
+ * Returns true if the start method supports idle.
+ */
+static inline bool tpm_crb_has_idle(u32 start_method)
+{
+	return !(start_method == ACPI_TPM2_START_METHOD ||
+	       start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD ||
+	       start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC);
+}
+
 static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
 				unsigned long timeout)
 {
@@ -173,9 +183,7 @@ static int __crb_go_idle(struct device *dev, struct crb_priv *priv)
 {
 	int rc;
 
-	if ((priv->sm == ACPI_TPM2_START_METHOD) ||
-	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
-	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
+	if (!tpm_crb_has_idle(priv->sm))
 		return 0;
 
 	iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
@@ -222,9 +230,7 @@ static int __crb_cmd_ready(struct device *dev, struct crb_priv *priv)
 {
 	int rc;
 
-	if ((priv->sm == ACPI_TPM2_START_METHOD) ||
-	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
-	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
+	if (!tpm_crb_has_idle(priv->sm))
 		return 0;
 
 	iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req);
@@ -423,13 +429,13 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
 	 * report only ACPI start but in practice seems to require both
 	 * CRB start, hence invoking CRB start method if hid == MSFT0101.
 	 */
-	if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
-	    (priv->sm == ACPI_TPM2_MEMORY_MAPPED) ||
-	    (!strcmp(priv->hid, "MSFT0101")))
+	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER ||
+	    priv->sm == ACPI_TPM2_MEMORY_MAPPED ||
+	    !strcmp(priv->hid, "MSFT0101"))
 		iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
 
-	if ((priv->sm == ACPI_TPM2_START_METHOD) ||
-	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD))
+	if (priv->sm == ACPI_TPM2_START_METHOD ||
+	    priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)
 		rc = crb_do_acpi_start(chip);
 
 	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
@@ -449,8 +455,8 @@ static void crb_cancel(struct tpm_chip *chip)
 
 	iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);
 
-	if (((priv->sm == ACPI_TPM2_START_METHOD) ||
-	    (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) &&
+	if ((priv->sm == ACPI_TPM2_START_METHOD ||
+	     priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) &&
 	     crb_do_acpi_start(chip))
 		dev_err(&chip->dev, "ACPI Start failed\n");
 }
@@ -609,8 +615,8 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
 	 * the control area, as one nice sane region except for some older
 	 * stuff that puts the control area outside the ACPI IO region.
 	 */
-	if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
-	    (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) {
+	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER ||
+	    priv->sm == ACPI_TPM2_MEMORY_MAPPED) {
 		if (iores &&
 		    buf->control_address == iores->start +
 		    sizeof(*priv->regs_h))