Re: [PATCH 2/2] slimbus: ngd: Add qcom SLIMBus NGD driver

From: Srinivas Kandagatla
Date: Mon May 21 2018 - 07:01:06 EST


Thanks Vinod for the review!

On 21/05/18 12:33, Vinod wrote:
On 16-05-18, 17:51, Srinivas Kandagatla wrote:
This patch adds suppor to Qualcomm SLIMBus Non-Generic Device (NGD)

/s/suppor/support

Yep, Will fix this in next version.

+/* NGD (Non-ported Generic Device) registers */
+#define NGD_CFG 0x0
+#define NGD_CFG_ENABLE BIT(0)
+#define NGD_CFG_RX_MSGQ_EN BIT(1)
+#define NGD_CFG_TX_MSGQ_EN BIT(2)
+#define NGD_STATUS 0x4
+#define NGD_LADDR BIT(1)
+#define NGD_RX_MSGQ_CFG 0x8
+#define NGD_INT_EN 0x10
+#define SLIMBUS_QMI_POWER_RESP_MAX_MSG_LEN 7
+#define SLIMBUS_QMI_SELECT_INSTANCE_REQ_MAX_MSG_LEN 14
+#define SLIMBUS_QMI_SELECT_INSTANCE_RESP_MAX_MSG_LEN 7
+#define SLIMBUS_QMI_CHECK_FRAMER_STAT_RESP_MAX_MSG_LEN 7
+/* QMI response timeout of 500ms */
+#define SLIMBUS_QMI_RESP_TOUT 1000

Tabs or spaces, take your pick and use one, not both...
I will check for such instances once again before sending v2.


+static void qcom_slim_qmi_power_resp_cb(struct qmi_handle *handle,
+ struct sockaddr_qrtr *sq,
+ struct qmi_txn *txn, const void *data)
+{
+ struct slimbus_power_resp_msg_v01 *resp;
+
+ resp = (struct slimbus_power_resp_msg_v01 *)data;

you dont need cast away from void
It's a const void * so the compiler keeps complaining about this without cast.


+ if (resp->resp.result != QMI_RESULT_SUCCESS_V01)
+ pr_err("%s: QMI power request failed 0x%x\n", __func__,
+ resp->resp.result);

cant we use dev_err?
I will have a look!

+static int qcom_slim_qmi_send_power_request(struct qcom_slim_ngd_ctrl *ctrl,
+ struct slimbus_power_req_msg_v01 *req)
+{
+ struct slimbus_power_resp_msg_v01 resp = { { 0, 0 } };
+ struct qmi_txn txn;
+ int rc;
+
+ rc = qmi_txn_init(ctrl->qmi.handle, &txn,
+ slimbus_power_resp_msg_v01_ei, &resp);
+
+ rc = qmi_send_request(ctrl->qmi.handle, NULL, &txn,
+ SLIMBUS_QMI_POWER_REQ_V01,
+ SLIMBUS_QMI_POWER_REQ_MAX_MSG_LEN,
+ slimbus_power_req_msg_v01_ei, req);
+ if (rc < 0) {
+ dev_err(ctrl->dev, "%s: QMI send req fail %d\n", __func__, rc);
+ qmi_txn_cancel(&txn);
+ }
+
+ if (rc < 0)
+ return rc;

why not add this is prev error check?
Yes, we should move this to previous check, Will fix this in v2.

+static int qcom_slim_qmi_init(struct qcom_slim_ngd_ctrl *ctrl,
+ bool apps_is_master)
+{
+ int rc = 0;

superfluous init

+static u32 *qcom_slim_ngd_tx_msg_get(struct qcom_slim_ngd_ctrl *ctrl, int len,
+ struct completion *comp)
+{
+ struct qcom_slim_ngd_dma_desc *desc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctrl->tx_buf_lock, flags);
+
+ if ((ctrl->tx_tail + 1) % QCOM_SLIM_NGD_DESC_NUM == ctrl->tx_head) {
+ spin_unlock_irqrestore(&ctrl->tx_buf_lock, flags);
+ return NULL;
+ }
+ desc = &ctrl->txdesc[ctrl->tx_tail];
+ desc->base = (u32 *)((u8 *)ctrl->tx_base +
+ (ctrl->tx_tail * SLIM_MSGQ_BUF_LEN));

too many casts

+static int qcom_slim_ngd_post_rx_msgq(struct qcom_slim_ngd_ctrl *ctrl)
+{
+ struct qcom_slim_ngd_dma_desc *desc;
+ struct dma_slave_config conf = {
+ .direction = DMA_DEV_TO_MEM,
+ };
+ int ret, i;
+
+ ret = dmaengine_slave_config(ctrl->dma_rx_channel, &conf);

so you are only setting direction for conf, not any other parameters? If not why
bother setting direction
Nice hint, I will remove this!

+ if (ret)
+ dev_err(ctrl->dev, "Error Configuring rx dma\n");
+
+ for (i = 0; i < QCOM_SLIM_NGD_DESC_NUM; i++) {
+ desc = &ctrl->rx_desc[i];
+ desc->phys = ctrl->rx_phys_base + i * SLIM_MSGQ_BUF_LEN;
+ desc->ctrl = ctrl;
+ desc->base = ctrl->rx_base + i * SLIM_MSGQ_BUF_LEN;
+ desc->desc = dmaengine_prep_slave_single(ctrl->dma_rx_channel,
+ desc->phys, SLIM_MSGQ_BUF_LEN,
+ DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT);

why issue multiple slave_single to dmaengine, you can bundle them and issue
dmaengine_prep_slave_sg()..
Am reusing the descriptors here, My plan is to issue multiple descriptors with callback for each, and in each callback queue it back.


+static int qcom_slim_ngd_qmi_svc_event_init(struct qcom_slim_ngd_qmi *qmi)
+{
+ int ret = 0;

superfluous init here too

Yep.
+static int qcom_slim_ngd_runtime_idle(struct device *dev)
+{
+ struct qcom_slim_ngd_ctrl *ctrl = dev_get_drvdata(dev);
+
+ if (ctrl->state == QCOM_SLIM_NGD_CTRL_AWAKE)
+ ctrl->state = QCOM_SLIM_NGD_CTRL_IDLE;
+ pm_request_autosuspend(dev);
+ return -EAGAIN;
+}
+
+

double empty lines, here
Sure, will fix this in v2.


thanks,
srini