Re: [PATCH v4 01/10] i3c: Add core I3C infrastructure

From: Boris Brezillon
Date: Mon Jun 04 2018 - 07:24:47 EST


On Mon, 4 Jun 2018 09:11:25 +0000
Przemyslaw Gaj <pgaj@xxxxxxxxxxx> wrote:

> Hi Boris
>
> It looks great, just one comment to DEFSLVS command:
>
> ïOn 6/4/18, 9:32 AM, "Boris Brezillon" <boris.brezillon@xxxxxxxxxxx> wrote:
>
> +int i3c_master_defslvs_locked(struct i3c_master_controller *master)
> +{
> + struct i3c_ccc_cmd_dest dest = {
> + .addr = I3C_BROADCAST_ADDR,
> + };
> + struct i3c_ccc_cmd cmd = {
> + .id = I3C_CCC_DEFSLVS,
> + .dests = &dest,
> + .ndests = 1,
> + };
> + struct i3c_ccc_defslvs *defslvs;
> + struct i3c_ccc_dev_desc *desc;
> + struct i3c_device *i3cdev;
> + struct i2c_device *i2cdev;
> + struct i3c_bus *bus;
> + bool send = false;
> + int ndevs = 0, ret;
> +
> + if (!master)
> + return -EINVAL;
> +
> + bus = i3c_master_get_bus(master);
> + i3c_bus_for_each_i3cdev(bus, i3cdev) {
> + ndevs++;
> + if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) == I3C_BCR_I3C_MASTER)
> + send = true;
> + }
> +
> + /* No other master on the bus, skip DEFSLVS. */
> + if (!send)
> + return 0;
> +
> + i3c_bus_for_each_i2cdev(bus, i2cdev)
> + ndevs++;
> +
> + dest.payload.len = sizeof(*defslvs) +
> + ((ndevs - 1) * sizeof(struct i3c_ccc_dev_desc));
> + defslvs = kzalloc(dest.payload.len, GFP_KERNEL);
> + if (!defslvs)
> + return -ENOMEM;
> +
> + dest.payload.data = defslvs;
> +
> + defslvs->count = ndevs;
> + defslvs->master.bcr = master->this->info.bcr;
> + defslvs->master.dcr = master->this->info.dcr;
> + defslvs->master.dyn_addr = master->this->info.dyn_addr;
> + defslvs->master.static_addr = I3C_BROADCAST_ADDR;
> +
> + desc = defslvs->slaves;
> + i3c_bus_for_each_i2cdev(bus, i2cdev) {
> + desc->lvr = i2cdev->lvr;
> + desc->static_addr = i2cdev->info.addr;
> + desc++;
> + }
> +
> + i3c_bus_for_each_i3cdev(bus, i3cdev) {
> + /* Skip the I3C dev representing this master. */
> + if (i3cdev == master->this)
> + continue;
> +
> + desc->bcr = i3cdev->info.bcr;
> + desc->dcr = i3cdev->info.dcr;
> + desc->dyn_addr = i3cdev->info.dyn_addr;
> + desc->static_addr = i3cdev->info.static_addr;
> + desc++;
> + }
> +
> + ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
> + kfree(defslvs);
> +
> + return ret;
> +}
>
> You should shift all the addresses (dynamic and static) one bit left.
> Addresses are stored on bits [7:1], this is described in MIPI spec,
> section 5.1.9.3.7 Define List of Slaves (DEFSLVS)

Oops, indeed. I will fix that.

Thanks,

Boris