On Tue, 14 Jun 2011 10:58:47 +0800
Kassey Lee <kassey1216@xxxxxxxxx> wrote:
> > +#include <linux/wait.h>
> > +#include <linux/delay.h>
> > +#include <linux/io.h>
> > +
> Would be good to sort headers alphabetically
Um, I suppose. You're sure you don't want inverse Christmas-tree ordering?
:)
> > +static int cafe_smbus_write_done(struct mcam_camera *mcam)
> > +{
> > + unsigned long flags;
> > + int c1;
> > +
> > + /*
> > + * We must delay after the interrupt, or the controller gets confused
> > + * and never does give us good status. Fortunately, we don't do this
> > + * often.
> > + */
> > + udelay(20);
> > + spin_lock_irqsave(&mcam->dev_lock, flags);
> > + c1 = mcam_reg_read(mcam, REG_TWSIC1);
> > + spin_unlock_irqrestore(&mcam->dev_lock, flags);
> do you really want to use spin_lock to protect REG_TWSIC1, this
> register is not access in ISR ?
I use the spinlock to protect all accesses to the MMIO space; I don't think
it makes sense to have multiple threads mucking around in there at ths same
time.
Also, once again, this is a reshuffle of code which has worked for years; I
don't think it's the right time to mess with the locking decisions.
> > +/*
> > + * Controller-level stuff
> > + */
> > +
> > +static void cafe_ctlr_init(struct mcam_camera *mcam)
> cafe_init is enough
Disagree. This is controller-level (as opposed to TWSI) programming, so
the related functions have "ctlr" in them. This doesn't seem like a level
of detail that needs a great deal of discussion...?
> > +#define cam_err(cam, fmt, arg...) \
> > + dev_err((cam)->dev, fmt, ##arg);
> > +#define cam_warn(cam, fmt, arg...) \
> > + dev_warn((cam)->dev, fmt, ##arg);
> > +#define cam_dbg(cam, fmt, arg...) \
> > + dev_dbg((cam)->dev, fmt, ##arg);
> > +
> you 've define these in cafe_driver.c, better to share one
Do look at the cafe version:
#define cam_err(cam, fmt, arg...) \
dev_err(&(cam)->pdev->dev, fmt, ##arg);
They're not the same, so can't be shared. Probably the cafe ones should be
renamed to cafe_err() or whatever to avoid this sort of confusion.
> > +static void mcam_ctlr_image(struct mcam_camera *cam)
> > +{
> > + int imgsz;
> > + struct v4l2_pix_format *fmt = &cam->pix_format;
> > +
> > + imgsz = ((fmt->height << IMGSZ_V_SHIFT) & IMGSZ_V_MASK) |
> > + (fmt->bytesperline & IMGSZ_H_MASK);
> Superfluous parenthesis
See http://lwn.net/Articles/382023/ :)
I feel that use of parentheses to make order of evaluation in complex
expressions explicit is no sin.
> > +static void mcam_ctlr_irq_enable(struct mcam_camera *cam)
> mcam_irq_enable is OK
Sure, it would be OK; there isn't the distinction with the TWSI IRQs that
the cafe driver has. I also don't think that the longer name contributes
greatly to global warming.
> > +/*
> > + * We have found the sensor on the i2c. Let's try to have a
> > + * conversation.
> > + */
> > +static int mcam_cam_init(struct mcam_camera *cam)
> > +{
> > + struct v4l2_dbg_chip_ident chip;
> > + int ret;
> > +
> > + mutex_lock(&cam->s_mutex);
> > + if (cam->state != S_NOTREADY)
> > + cam_warn(cam, "Cam init with device in funky state %d",
> > + cam->state);
> > + ret = __mcam_cam_reset(cam);
> > + if (ret)
> > + goto out;
> > + chip.ident = V4L2_IDENT_NONE;
> > + chip.match.type = V4L2_CHIP_MATCH_I2C_ADDR;
> > + chip.match.addr = cam->sensor_addr;
> > + ret = sensor_call(cam, core, g_chip_ident, &chip);
> > + if (ret)
> > + goto out;
> > + cam->sensor_type = chip.ident;
> > + if (cam->sensor_type != V4L2_IDENT_OV7670) {
> again, CCIC do not need to know sensor's name.
And, again, that will be fixed. But that's a job for a separate patch.
> > +static int mcam_vidioc_reqbufs(struct file *filp, void *priv,
> > + struct v4l2_requestbuffers *req)
> > +{
> > + struct mcam_camera *cam = filp->private_data;
> > + int ret = 0; /* Silence warning */
> > +
> > + /*
> > + * Make sure it's something we can do. User pointers could be
> > + * implemented without great pain, but that's not been done yet.
> > + */
> > + if (req->memory != V4L2_MEMORY_MMAP)
> > + return -EINVAL;
> only MMAP ?
Yes, the current code doesn't do USERPTR, never has. The vb2 conversion
(already working in my tree here, BTW) will fix that.
> > +static int mcam_vidioc_qbuf(struct file *filp, void *priv,
> > + struct v4l2_buffer *buf)
> > +{
> > + struct mcam_camera *cam = filp->private_data;
> > + struct mcam_sio_buffer *sbuf;
> > + int ret = -EINVAL;
> > + unsigned long flags;
> > +
> > + mutex_lock(&cam->s_mutex);
> > + if (buf->index >= cam->n_sbufs)
> > + goto out;
> > + sbuf = cam->sb_bufs + buf->index;
> > + if (sbuf->v4lbuf.flags & V4L2_BUF_FLAG_QUEUED) {
> > + ret = 0; /* Already queued?? */
> > + goto out;
> > + }
> > + if (sbuf->v4lbuf.flags & V4L2_BUF_FLAG_DONE) {
> > + /* Spec doesn't say anything, seems appropriate tho */
> > + ret = -EBUSY;
> > + goto out;
> > + }
> > + sbuf->v4lbuf.flags |= V4L2_BUF_FLAG_QUEUED;
> > + spin_lock_irqsave(&cam->dev_lock, flags);
> > + list_add(&sbuf->list, &cam->sb_avail);
> list_add_tail is better.
I would dispute that - I'd rather reuse cache-hot buffers. But it's
totally irrelevant; all this buffer-handling code is headed for the bit
bucket with vb2.
> > +static int mcam_vidioc_querycap(struct file *file, void *priv,
> > + struct v4l2_capability *cap)
> > +{
> > + strcpy(cap->driver, "marvell_ccic");
> > + strcpy(cap->card, "marvell_ccic");
> strlcpy is better
Why? There's no mystery about the length of the string.
> > +static int mcam_vidioc_enum_input(struct file *filp, void *priv,
> > + struct v4l2_input *input)
> > +{
> > + if (input->index != 0)
> > + return -EINVAL;
> > +
> > + input->type = V4L2_INPUT_TYPE_CAMERA;
> > + input->std = V4L2_STD_ALL; /* Not sure what should go here */
> > + strcpy(input->name, "Camera");
> strlcpy
Ditto.
> > +int mccic_register(struct mcam_camera *cam)
> > +{
> > + struct i2c_board_info ov7670_info = {
> > + .type = "ov7670",
> > + .addr = 0x42,
> > + .platform_data = &sensor_cfg,
> > + };
> you can put this in board.c
Agreed, that's exactly where it needs to be. Or in the device tree, if
that's in use. All that will be done when the ov7670 dependency is
removed.
> > + /*
> > + * Try to find the sensor.
> > + */
> > + cam->sensor_addr = ov7670_info.addr;
> > + cam->sensor = v4l2_i2c_new_subdev_board(&cam->v4l2_dev,
> > + &cam->i2c_adapter, &ov7670_info, NULL);
> I do not thinks so.
I don't understand what this comment is meant to mean...?
> > +/*
> > + * Register I/O functions. These are here because the platform code
> > + * may legitimately need to mess with the register space.
> > + */
> > +/*
> > + * Device register I/O
> > + */
> > +static inline void mcam_reg_write(struct mcam_camera *cam, unsigned int reg,
> > + unsigned int val)
> u32 val
*shrug*, that would work too, yes.
Thanks,
jon
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