net: ipa: reduce IPA version assumptions

Modify conditional tests throughout the IPA code so they do not
assume that IPA v3.5.1 is the oldest version supported.  Also remove
assumptions that IPA v4.5 is the newest version of IPA supported.

Augment versions in comments with "+", to be clearer that the
comment applies to a version and subsequent versions.  (E.g.,
"present for IPA v4.2+" instead of just "present for v4.2".)

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 11 deletions

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index 88310d358557..5f93bd60c758 100644
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -266,7 +266,7 @@ ipa_endpoint_init_ctrl(struct ipa_endpoint *endpoint, bool suspend_delay)
 	 * if (endpoint->toward_ipa)
 	 * 	assert(ipa->version != IPA_VERSION_4.2);
 	 * else
-	 * 	assert(ipa->version == IPA_VERSION_3_5_1);
+	 *	assert(ipa->version < IPA_VERSION_4_0);
 	 */
 	mask = endpoint->toward_ipa ? ENDP_DELAY_FMASK : ENDP_SUSPEND_FMASK;
 
@@ -347,7 +347,7 @@ ipa_endpoint_program_suspend(struct ipa_endpoint *endpoint, bool enable)
 {
 	bool suspended;
 
-	if (endpoint->ipa->version != IPA_VERSION_3_5_1)
+	if (endpoint->ipa->version >= IPA_VERSION_4_0)
 		return enable;	/* For IPA v4.0+, no change made */
 
 	/* assert(!endpoint->toward_ipa); */
@@ -515,7 +515,7 @@ static void ipa_endpoint_init_hdr(struct ipa_endpoint *endpoint)
 			/* Where IPA will write the length */
 			offset = offsetof(struct rmnet_map_header, pkt_len);
 			/* Upper bits are stored in HDR_EXT with IPA v4.5 */
-			if (version == IPA_VERSION_4_5)
+			if (version >= IPA_VERSION_4_5)
 				offset &= field_mask(HDR_OFST_PKT_SIZE_FMASK);
 
 			val |= HDR_OFST_PKT_SIZE_VALID_FMASK;
@@ -562,7 +562,7 @@ static void ipa_endpoint_init_hdr_ext(struct ipa_endpoint *endpoint)
 	/* IPA v4.5 adds some most-significant bits to a few fields,
 	 * two of which are defined in the HDR (not HDR_EXT) register.
 	 */
-	if (ipa->version == IPA_VERSION_4_5) {
+	if (ipa->version >= IPA_VERSION_4_5) {
 		/* HDR_TOTAL_LEN_OR_PAD_OFFSET is 0, so MSB is 0 */
 		if (endpoint->data->qmap && !endpoint->toward_ipa) {
 			u32 offset;
@@ -776,7 +776,7 @@ static u32 hol_block_timer_val(struct ipa *ipa, u32 microseconds)
 	if (!microseconds)
 		return 0;	/* Nothing to compute if timer period is 0 */
 
-	if (ipa->version == IPA_VERSION_4_5)
+	if (ipa->version >= IPA_VERSION_4_5)
 		return hol_block_timer_qtime_val(ipa, microseconds);
 
 	/* Use 64 bit arithmetic to avoid overflow... */
@@ -1468,8 +1468,7 @@ static void ipa_endpoint_reset(struct ipa_endpoint *endpoint)
 	 * is active, we need to handle things specially to recover.
 	 * All other cases just need to reset the underlying GSI channel.
 	 */
-	special = ipa->version == IPA_VERSION_3_5_1 &&
-			!endpoint->toward_ipa &&
+	special = ipa->version < IPA_VERSION_4_0 && !endpoint->toward_ipa &&
 			endpoint->data->aggregation;
 	if (special && ipa_endpoint_aggr_active(endpoint))
 		ret = ipa_endpoint_reset_rx_aggr(endpoint);
@@ -1567,8 +1566,10 @@ void ipa_endpoint_suspend_one(struct ipa_endpoint *endpoint)
 		(void)ipa_endpoint_program_suspend(endpoint, true);
 	}
 
-	/* IPA v3.5.1 doesn't use channel stop for suspend */
-	stop_channel = endpoint->ipa->version != IPA_VERSION_3_5_1;
+	/* Starting with IPA v4.0, endpoints are suspended by stopping the
+	 * underlying GSI channel rather than using endpoint suspend mode.
+	 */
+	stop_channel = endpoint->ipa->version >= IPA_VERSION_4_0;
 	ret = gsi_channel_suspend(gsi, endpoint->channel_id, stop_channel);
 	if (ret)
 		dev_err(dev, "error %d suspending channel %u\n", ret,
@@ -1588,8 +1589,10 @@ void ipa_endpoint_resume_one(struct ipa_endpoint *endpoint)
 	if (!endpoint->toward_ipa)
 		(void)ipa_endpoint_program_suspend(endpoint, false);
 
-	/* IPA v3.5.1 doesn't use channel start for resume */
-	start_channel = endpoint->ipa->version != IPA_VERSION_3_5_1;
+	/* Starting with IPA v4.0, the underlying GSI channel must be
+	 * restarted for resume.
+	 */
+	start_channel = endpoint->ipa->version >= IPA_VERSION_4_0;
 	ret = gsi_channel_resume(gsi, endpoint->channel_id, start_channel);
 	if (ret)
 		dev_err(dev, "error %d resuming channel %u\n", ret,