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power: supply: bd71828: Support wider register addresses

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The BD71828 power-supply driver assumes register addresses to be 8-bit.
The new BD72720 will use stacked register maps to hide paging which is
done using secondary I2C slave address. This requires use of 9-bit
register addresses in the power-supply driver (added offset 0x100 to
the 8-bit hardware register addresses).

The cost is slightly used memory consumption as the members in the
struct pwr_regs will be changed from u8 to unsigned int, which means 3
byte increase / member / instance.
This is currently 14 members (expected to possibly be increased when
adding new variants / new functionality which may introduce new
registers, but not expected to grow much) and 2 instances (will be 3
instances when BD72720 gets added).

So, even if the number of registers grew to 50 it'd be 150 bytes /
instance. Assuming we eventually supported 5 variants, it'd be
5 * 150 bytes, which stays very reasonable considering systems we are
dealing with.

As a side note, we can reduce the "wasted space / member / instance" from
3 bytes to 1 byte, by using u16 instead of the unsigned int if needed. I
rather use unsigned int to be initially prepared for devices with 32 bit
registers if there is no need to count bytes.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://patch.msgid.link/57c87f7e2082a666f0adeafcd11f673c0af7d326.1765804226.git.mazziesaccount@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
This commit is contained in:
Matti Vaittinen
2025-12-15 15:21:03 +02:00
committed by Lee Jones
parent 0234e0033e
commit de8f20afb0
1 changed files with 13 additions and 13 deletions
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26
drivers/power/supply/bd71828-power.c
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@@ -44,19 +44,19 @@
#define VBAT_LOW_TH 0x00D4
struct pwr_regs {
u8 vbat_avg;
u8 ibat;
u8 ibat_avg;
u8 btemp_vth;
u8 chg_state;
u8 bat_temp;
u8 dcin_stat;
u8 dcin_collapse_limit;
u8 chg_set1;
u8 chg_en;
u8 vbat_alm_limit_u;
u8 conf;
u8 vdcin;
unsigned int vbat_avg;
unsigned int ibat;
unsigned int ibat_avg;
unsigned int btemp_vth;
unsigned int chg_state;
unsigned int bat_temp;
unsigned int dcin_stat;
unsigned int dcin_collapse_limit;
unsigned int chg_set1;
unsigned int chg_en;
unsigned int vbat_alm_limit_u;
unsigned int conf;
unsigned int vdcin;
};
static const struct pwr_regs pwr_regs_bd71828 = {