On Fri, 17 Apr 2020 18:20:52 +0200
Parshuram Thombare <pthom...@cadence.com> wrote:
> To support mastership handover procedure, this patch splits the
> bus_init callback into bus_init and master_set_info callbacks
Missing period at the end of this sentence.
IIRC, we discussed passing master info directly at controller
registration time for primary master registration, thus avoiding this
->master_set_info() step. Any good reason for doing that? I mean, I'd
expect the PID, BCR, DCR to be fixed, the only one that can be assigned
automatically is the address, and we can have a magic value for
'auto-assign the first available address', like '0'. The
write to DEV_ID_RR0() can be done conditionally in master_bus_init()
when '!secondary_master'.
>
> Signed-off-by: Parshuram Thombare <pthom...@cadence.com>
> ---
> drivers/i3c/master.c | 10 +++--
> drivers/i3c/master/dw-i3c-master.c | 29 ++++++++-----
> drivers/i3c/master/i3c-master-cdns.c | 63 ++++++++++++++++++----------
> include/linux/i3c/master.h | 7 +++-
> 4 files changed, 71 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 5f4bd52121fe..0ec332e45737 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -1716,6 +1716,10 @@ static int i3c_master_bus_init(struct
> i3c_master_controller *master)
> if (ret)
> goto err_detach_devs;
>
> + ret = master->ops->master_set_info(master);
> + if (ret)
> + goto err_detach_devs;
> +
> /*
> * The master device should have been instantiated in ->bus_init(),
> * complain if this was not the case.
> @@ -2378,9 +2382,9 @@ EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot);
>
> static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops)
> {
> - if (!ops || !ops->bus_init || !ops->priv_xfers ||
> - !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers ||
> - !ops->i2c_funcs)
> + if (!ops || !ops->bus_init || !ops->master_set_info ||
> + !ops->priv_xfers || !ops->send_ccc_cmd || !ops->do_daa ||
> + !ops->i2c_xfers || !ops->i2c_funcs)
> return -EINVAL;
>
> if (ops->request_ibi &&
> diff --git a/drivers/i3c/master/dw-i3c-master.c
> b/drivers/i3c/master/dw-i3c-master.c
> index 1d83c97431c7..5c9a72d68fb8 100644
> --- a/drivers/i3c/master/dw-i3c-master.c
> +++ b/drivers/i3c/master/dw-i3c-master.c
> @@ -593,7 +593,6 @@ static int dw_i3c_master_bus_init(struct
> i3c_master_controller *m)
> {
> struct dw_i3c_master *master = to_dw_i3c_master(m);
> struct i3c_bus *bus = i3c_master_get_bus(m);
> - struct i3c_device_info info = { };
> u32 thld_ctrl;
> int ret;
>
> @@ -624,6 +623,24 @@ static int dw_i3c_master_bus_init(struct
> i3c_master_controller *m)
> writel(INTR_MASTER_MASK, master->regs + INTR_STATUS_EN);
> writel(INTR_MASTER_MASK, master->regs + INTR_SIGNAL_EN);
>
> + writel(IBI_REQ_REJECT_ALL, master->regs + IBI_SIR_REQ_REJECT);
> + writel(IBI_REQ_REJECT_ALL, master->regs + IBI_MR_REQ_REJECT);
> +
> + /* For now don't support Hot-Join */
> + writel(readl(master->regs + DEVICE_CTRL) | DEV_CTRL_HOT_JOIN_NACK,
> + master->regs + DEVICE_CTRL);
> +
> + dw_i3c_master_enable(master);
> +
> + return 0;
> +}
> +
> +static int dw_i3c_master_set_info(struct i3c_master_controller *m)
> +{
> + struct dw_i3c_master *master = to_dw_i3c_master(m);
> + struct i3c_device_info info = { };
> + int ret;
> +
> ret = i3c_master_get_free_addr(m, 0);
> if (ret < 0)
> return ret;
> @@ -638,15 +655,6 @@ static int dw_i3c_master_bus_init(struct
> i3c_master_controller *m)
> if (ret)
> return ret;
>
> - writel(IBI_REQ_REJECT_ALL, master->regs + IBI_SIR_REQ_REJECT);
> - writel(IBI_REQ_REJECT_ALL, master->regs + IBI_MR_REQ_REJECT);
> -
> - /* For now don't support Hot-Join */
> - writel(readl(master->regs + DEVICE_CTRL) | DEV_CTRL_HOT_JOIN_NACK,
> - master->regs + DEVICE_CTRL);
> -
> - dw_i3c_master_enable(master);
> -
> return 0;
> }
>
> @@ -1088,6 +1096,7 @@ static irqreturn_t dw_i3c_master_irq_handler(int irq,
> void *dev_id)
>
> static const struct i3c_master_controller_ops dw_mipi_i3c_ops = {
> .bus_init = dw_i3c_master_bus_init,
> + .master_set_info = dw_i3c_master_set_info,
> .bus_cleanup = dw_i3c_master_bus_cleanup,
> .attach_i3c_dev = dw_i3c_master_attach_i3c_dev,
> .reattach_i3c_dev = dw_i3c_master_reattach_i3c_dev,
> diff --git a/drivers/i3c/master/i3c-master-cdns.c
> b/drivers/i3c/master/i3c-master-cdns.c
> index 8889a4fdb454..c2d1631a9e38 100644
> --- a/drivers/i3c/master/i3c-master-cdns.c
> +++ b/drivers/i3c/master/i3c-master-cdns.c
> @@ -1199,21 +1199,20 @@ static int cdns_i3c_master_bus_init(struct
> i3c_master_controller *m)
> struct cdns_i3c_master *master = to_cdns_i3c_master(m);
> unsigned long pres_step, sysclk_rate, max_i2cfreq;
> struct i3c_bus *bus = i3c_master_get_bus(m);
> - u32 ctrl, prescl0, prescl1, pres, low;
> - struct i3c_device_info info = { };
> - int ret, ncycles;
> + u32 ctrl, prescl0, prescl1, pres, low, bus_mode;
> + int ncycles;
>
> switch (bus->mode) {
> case I3C_BUS_MODE_PURE:
> - ctrl = CTRL_PURE_BUS_MODE;
> + bus_mode = CTRL_PURE_BUS_MODE;
> break;
>
> case I3C_BUS_MODE_MIXED_FAST:
> - ctrl = CTRL_MIXED_FAST_BUS_MODE;
> + bus_mode = CTRL_MIXED_FAST_BUS_MODE;
> break;
>
> case I3C_BUS_MODE_MIXED_SLOW:
> - ctrl = CTRL_MIXED_SLOW_BUS_MODE;
> + bus_mode = CTRL_MIXED_SLOW_BUS_MODE;
> break;
>
> default:
> @@ -1244,7 +1243,6 @@ static int cdns_i3c_master_bus_init(struct
> i3c_master_controller *m)
> bus->scl_rate.i2c = sysclk_rate / ((pres + 1) * 5);
>
> prescl0 |= PRESCL_CTRL0_I2C(pres);
> - writel(prescl0, master->regs + PRESCL_CTRL0);
>
> /* Calculate OD and PP low. */
> pres_step = 1000000000 / (bus->scl_rate.i3c * 4);
> @@ -1252,15 +1250,43 @@ static int cdns_i3c_master_bus_init(struct
> i3c_master_controller *m)
> if (ncycles < 0)
> ncycles = 0;
> prescl1 = PRESCL_CTRL1_OD_LOW(ncycles);
> +
> + ctrl = readl(master->regs + CTRL);
> + if (ctrl & CTRL_DEV_EN)
> + cdns_i3c_master_disable(master);
> + writel(prescl0, master->regs + PRESCL_CTRL0);
> writel(prescl1, master->regs + PRESCL_CTRL1);
> + ctrl &= ~CTRL_BUS_MODE_MASK;
> + ctrl |= bus_mode | CTRL_HALT_EN | CTRL_MCS_EN;
> + /*
> + * Enable Hot-Join, and, when a Hot-Join request happens,
> + * disable all events coming from this device.
> + * We will issue ENTDAA afterwards from the threaded IRQ
> + * handler.
> + */
> + if (!m->secondary)
> + ctrl |= CTRL_HJ_ACK | CTRL_HJ_DISEC;
> + writel(ctrl, master->regs + CTRL);
> + cdns_i3c_master_enable(master);
>
> - /* Get an address for the master. */
> - ret = i3c_master_get_free_addr(m, 0);
> - if (ret < 0)
> - return ret;
> + return 0;
> +}
>
> - writel(prepare_rr0_dev_address(ret) | DEV_ID_RR0_IS_I3C,
> - master->regs + DEV_ID_RR0(0));
> +static int cdns_i3c_master_set_info(struct i3c_master_controller *m)
> +{
> + struct cdns_i3c_master *master = to_cdns_i3c_master(m);
> + struct i3c_device_info info = { };
> + int ret;
> +
> + if (!m->secondary) {
> + /* Get an address for the master. */
> + ret = i3c_master_get_free_addr(m, 0);
> + if (ret < 0)
> + return ret;
> +
> + writel(prepare_rr0_dev_address(ret) | DEV_ID_RR0_IS_I3C,
> + master->regs + DEV_ID_RR0(0));
> + }
>
> cdns_i3c_master_dev_rr_to_info(master, 0, &info);
> if (info.bcr & I3C_BCR_HDR_CAP)
> @@ -1270,16 +1296,6 @@ static int cdns_i3c_master_bus_init(struct
> i3c_master_controller *m)
> if (ret)
> return ret;
>
> - /*
> - * Enable Hot-Join, and, when a Hot-Join request happens, disable all
> - * events coming from this device.
> - *
> - * We will issue ENTDAA afterwards from the threaded IRQ handler.
> - */
> - ctrl |= CTRL_HJ_ACK | CTRL_HJ_DISEC | CTRL_HALT_EN | CTRL_MCS_EN;
> - writel(ctrl, master->regs + CTRL);
> -
> - cdns_i3c_master_enable(master);
>
> return 0;
> }
> @@ -1507,6 +1523,7 @@ static void cdns_i3c_master_recycle_ibi_slot(struct
> i3c_dev_desc *dev,
>
> static const struct i3c_master_controller_ops cdns_i3c_master_ops = {
> .bus_init = cdns_i3c_master_bus_init,
> + .master_set_info = cdns_i3c_master_set_info,
> .bus_cleanup = cdns_i3c_master_bus_cleanup,
> .do_daa = cdns_i3c_master_do_daa,
> .attach_i3c_dev = cdns_i3c_master_attach_i3c_dev,
> diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
> index f13fd8b1dd79..3dc7eafe811a 100644
> --- a/include/linux/i3c/master.h
> +++ b/include/linux/i3c/master.h
> @@ -337,10 +337,12 @@ struct i3c_bus {
>
> /**
> * struct i3c_master_controller_ops - I3C master methods
> - * @bus_init: hook responsible for the I3C bus initialization. You should at
> - * least call master_set_info() from there and set the bus mode.
> + * @bus_init: hook responsible for the I3C bus initialization.
> * You can also put controller specific initialization in there.
> * This method is mandatory.
> + * @master_set_info: hook responsible for assigning address to main master.
> + * You should call i3c_master_set_info from here.
> + * This method is mandatory.
> * @bus_cleanup: cleanup everything done in
> * &i3c_master_controller_ops->bus_init().
> * This method is optional.
> @@ -421,6 +423,7 @@ struct i3c_bus {
> */
> struct i3c_master_controller_ops {
> int (*bus_init)(struct i3c_master_controller *master);
> + int (*master_set_info)(struct i3c_master_controller *m);
> void (*bus_cleanup)(struct i3c_master_controller *master);
> int (*attach_i3c_dev)(struct i3c_dev_desc *dev);
> int (*reattach_i3c_dev)(struct i3c_dev_desc *dev, u8 old_dyn_addr);
