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

[Srinivas Kandagatla]

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