lkml.org 
[lkml]   [2017]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [RFC PATCH v2 6/7] typec: tcpm: Represent source supply through power_supply class
Date
On 25 November 2017 14:03, Hans de Goede wrote:

> Hi,
>
> On 11/24/2017 01:19 PM, Heikki Krogerus wrote:
> > Hi,
> >
> > On Tue, Nov 14, 2017 at 11:44:47AM +0000, Adam Thomson wrote:
> >> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> >> index 78983e1..7c26c3d 100644
> >> --- a/drivers/usb/typec/tcpm.c
> >> +++ b/drivers/usb/typec/tcpm.c
> >> @@ -12,6 +12,7 @@
> >> #include <linux/kernel.h>
> >> #include <linux/module.h>
> >> #include <linux/mutex.h>
> >> +#include <linux/power_supply.h>
> >> #include <linux/proc_fs.h>
> >> #include <linux/sched/clock.h>
> >> #include <linux/seq_file.h>
> >> @@ -277,6 +278,10 @@ struct tcpm_port {
> >> u32 current_limit;
> >> u32 supply_voltage;
> >>
> >> + /* Used to export TA voltage and current */
> >> + struct power_supply *psy;
> >> + struct power_supply_desc psy_desc;
> >> +
> >> u32 bist_request;
> >>
> >> /* PD state for Vendor Defined Messages */
> >> @@ -1756,6 +1761,7 @@ static int tcpm_pd_select_pdo(struct tcpm_port *port)
> >> int ret = -EINVAL;
> >>
> >> port->pps_data.supported = false;
> >> + port->psy_desc.type = POWER_SUPPLY_TYPE_USB_PD;
> >>
> >> /*
> >> * Select the source PDO providing the most power while staying within
> >> @@ -1775,8 +1781,10 @@ static int tcpm_pd_select_pdo(struct tcpm_port
> *port)
> >> mv = pdo_min_voltage(pdo);
> >> break;
> >> case PDO_TYPE_APDO:
> >> - if (pdo_apdo_type(pdo) == APDO_TYPE_PPS)
> >> + if (pdo_apdo_type(pdo) == APDO_TYPE_PPS) {
> >> port->pps_data.supported = true;
> >> + port->psy_desc.type =
> POWER_SUPPLY_TYPE_USB_PD_PPS;
> >> + }
> >> continue;
> >> default:
> >> tcpm_log(port, "Invalid PDO type, ignoring");
> >> @@ -2248,6 +2256,9 @@ static void tcpm_reset_port(struct tcpm_port *port)
> >> port->try_snk_count = 0;
> >> port->supply_voltage = 0;
> >> port->current_limit = 0;
> >> + port->psy_desc.type = POWER_SUPPLY_TYPE_USB_TYPE_C;
> >
> > Is it OK to everybody that the type of the psy is changed like that?
> > Hans?!
> >
> > We do have drivers that already change the type, for example
> > drivers/power/supply/isp1704_charger.c, but what does the user space
> > expect? The ABI for the power supply class was never documented I
> > guess.
>
> The main userspace consumer of the power_supply sysfs class is upower,
> upower knows about 3 types: "Mains", "Battery" and "USB", anything
> else it gives a type of UP_DEVICE_KIND_UNKNOWN. So
> POWER_SUPPLY_TYPE_USB_TYPE_C
> vs POWER_SUPPLY_TYPE_USB_PD_PPS does matter to it.

Does or doesn't matter? I had a quick look at the code for upower and if I
understand correctly right now both USB_TYPE_C and USB_PD_PPS would be
represented as 'UP_DEVICE_KIND_UNKNOWN' based on g_ascii_strcasecmp result. Is
that correct?
\
 
 \ /
  Last update: 2017-11-27 14:44    [W:0.077 / U:2.004 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site