| Message ID | 20220603135714.12007-2-aidanmacdonald.0x0@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add support for AXP192 PMIC | expand |
On Fri, Jun 03, 2022 at 02:57:05PM +0100, Aidan MacDonald wrote: > Add a new callback, get_irq_reg, for regmap IRQ chips, to support devices > with unusual register layouts. This is required in the rare cases where > the offset of an IRQ register is not constant with respect to the base > register. This is probably best illustrated with an example: > > mask status > IRQ0 0x40 0x44 > IRQ1 0x41 0x45 > IRQ2 0x42 0x46 > IRQ3 0x43 0x47 > IRQ4 0x4a 0x4d > > If we set mask_base = 0x40 and status_base = 0x44, the offsets of each > register relative to the base are: > > mask status > IRQ0 0 0 > IRQ1 1 1 > IRQ2 2 2 > IRQ3 3 3 > IRQ4 10 9 > > The existing mapping mechanisms can't include IRQ4 in the same irqchip > as IRQ0-3 because the offset of IRQ4's register depends on which type > of register we're asking for, ie. which base register is used. > > The get_irq_reg callback allows drivers to specify an arbitrary mapping > of (base register, register index) pairs to register addresses, instead > of the default linear mapping "base_register + register_index". This > allows unusual layouts, like the one above, to be handled using a single > regmap IRQ chip. > > The drawback is that when get_irq_reg is used, it's impossible to use > bulk reads for status registers even if some of them are contiguous, > because the mapping is opaque to regmap-irq. This should be acceptable > for the case of a few infrequently-polled status registers. This patch does two things: 1. Add a new callback `get_irq_reg` 2. Replace unmask_offset calculation with call to sub_irq_reg() Could you please split the patch into two to better reflect this? Thank you. Guru Das.
Guru Das Srinagesh <quic_gurus@quicinc.com> writes: > On Fri, Jun 03, 2022 at 02:57:05PM +0100, Aidan MacDonald wrote: >> Add a new callback, get_irq_reg, for regmap IRQ chips, to support devices >> with unusual register layouts. This is required in the rare cases where >> the offset of an IRQ register is not constant with respect to the base >> register. This is probably best illustrated with an example: >> >> mask status >> IRQ0 0x40 0x44 >> IRQ1 0x41 0x45 >> IRQ2 0x42 0x46 >> IRQ3 0x43 0x47 >> IRQ4 0x4a 0x4d >> >> If we set mask_base = 0x40 and status_base = 0x44, the offsets of each >> register relative to the base are: >> >> mask status >> IRQ0 0 0 >> IRQ1 1 1 >> IRQ2 2 2 >> IRQ3 3 3 >> IRQ4 10 9 >> >> The existing mapping mechanisms can't include IRQ4 in the same irqchip >> as IRQ0-3 because the offset of IRQ4's register depends on which type >> of register we're asking for, ie. which base register is used. >> >> The get_irq_reg callback allows drivers to specify an arbitrary mapping >> of (base register, register index) pairs to register addresses, instead >> of the default linear mapping "base_register + register_index". This >> allows unusual layouts, like the one above, to be handled using a single >> regmap IRQ chip. >> >> The drawback is that when get_irq_reg is used, it's impossible to use >> bulk reads for status registers even if some of them are contiguous, >> because the mapping is opaque to regmap-irq. This should be acceptable >> for the case of a few infrequently-polled status registers. > > This patch does two things: > > 1. Add a new callback `get_irq_reg` > 2. Replace unmask_offset calculation with call to sub_irq_reg() > > Could you please split the patch into two to better reflect this? > > Thank you. > > Guru Das. No problem, I'll do that in my v2. Regards, Aidan
diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c index 400c7412a7dc..e50437b18284 100644 --- a/drivers/base/regmap/regmap-irq.c +++ b/drivers/base/regmap/regmap-irq.c @@ -55,7 +55,9 @@ static int sub_irq_reg(struct regmap_irq_chip_data *data, unsigned int offset; int reg = 0; - if (!chip->sub_reg_offsets || !chip->not_fixed_stride) { + if (chip->get_irq_reg) { + reg = chip->get_irq_reg(base_reg, i); + } else if (!chip->sub_reg_offsets || !chip->not_fixed_stride) { /* Assume linear mapping */ reg = base_reg + (i * map->reg_stride * data->irq_reg_stride); } else { @@ -97,7 +99,6 @@ static void regmap_irq_sync_unlock(struct irq_data *data) struct regmap *map = d->map; int i, j, ret; u32 reg; - u32 unmask_offset; u32 val; if (d->chip->runtime_pm) { @@ -141,11 +142,11 @@ static void regmap_irq_sync_unlock(struct irq_data *data) dev_err(d->map->dev, "Failed to sync unmasks in %x\n", reg); - unmask_offset = d->chip->unmask_base - - d->chip->mask_base; + /* clear mask with unmask_base register */ + reg = sub_irq_reg(d, d->chip->unmask_base, i); ret = regmap_irq_update_bits(d, - reg + unmask_offset, + reg, d->mask_buf_def[i], d->mask_buf[i]); } else { @@ -480,7 +481,7 @@ static irqreturn_t regmap_irq_thread(int irq, void *d) } } else if (!map->use_single_read && map->reg_stride == 1 && - data->irq_reg_stride == 1) { + data->irq_reg_stride == 1 && !chip->get_irq_reg) { u8 *buf8 = data->status_reg_buf; u16 *buf16 = data->status_reg_buf; @@ -632,7 +633,6 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode, int ret = -ENOMEM; int num_type_reg; u32 reg; - u32 unmask_offset; if (chip->num_regs <= 0) return -EINVAL; @@ -773,10 +773,9 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode, ret = regmap_irq_update_bits(d, reg, d->mask_buf[i], ~d->mask_buf[i]); else if (d->chip->unmask_base) { - unmask_offset = d->chip->unmask_base - - d->chip->mask_base; + reg = sub_irq_reg(d, d->chip->unmask_base, i); ret = regmap_irq_update_bits(d, - reg + unmask_offset, + reg, d->mask_buf[i], d->mask_buf[i]); } else diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 8952fa3d0d59..4828021ab9e8 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -1495,6 +1495,10 @@ struct regmap_irq_sub_irq_map { * after handling the interrupts in regmap_irq_handler(). * @set_type_virt: Driver specific callback to extend regmap_irq_set_type() * and configure virt regs. + * @get_irq_reg: Callback to map a register index in range [0, num_regs[ + * to a register, relative to a specific base register. This + * is mainly useful for devices where the register offsets + * change depending on the base register. * @irq_drv_data: Driver specific IRQ data which is passed as parameter when * driver specific pre/post interrupt handler is called. * @@ -1545,6 +1549,7 @@ struct regmap_irq_chip { int (*handle_post_irq)(void *irq_drv_data); int (*set_type_virt)(unsigned int **buf, unsigned int type, unsigned long hwirq, int reg); + int (*get_irq_reg)(unsigned int base_reg, int i); void *irq_drv_data; };
Add a new callback, get_irq_reg, for regmap IRQ chips, to support devices with unusual register layouts. This is required in the rare cases where the offset of an IRQ register is not constant with respect to the base register. This is probably best illustrated with an example: mask status IRQ0 0x40 0x44 IRQ1 0x41 0x45 IRQ2 0x42 0x46 IRQ3 0x43 0x47 IRQ4 0x4a 0x4d If we set mask_base = 0x40 and status_base = 0x44, the offsets of each register relative to the base are: mask status IRQ0 0 0 IRQ1 1 1 IRQ2 2 2 IRQ3 3 3 IRQ4 10 9 The existing mapping mechanisms can't include IRQ4 in the same irqchip as IRQ0-3 because the offset of IRQ4's register depends on which type of register we're asking for, ie. which base register is used. The get_irq_reg callback allows drivers to specify an arbitrary mapping of (base register, register index) pairs to register addresses, instead of the default linear mapping "base_register + register_index". This allows unusual layouts, like the one above, to be handled using a single regmap IRQ chip. The drawback is that when get_irq_reg is used, it's impossible to use bulk reads for status registers even if some of them are contiguous, because the mapping is opaque to regmap-irq. This should be acceptable for the case of a few infrequently-polled status registers. Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com> --- drivers/base/regmap/regmap-irq.c | 19 +++++++++---------- include/linux/regmap.h | 5 +++++ 2 files changed, 14 insertions(+), 10 deletions(-)