On 3/30/23 10:35, Greg KH wrote:
On Thu, Mar 30, 2023 at 10:20:06AM +0200, Julien Panis wrote:
This PFSM controls the operational modes of the PMIC:
- STANDBY and LP_STANDBY,
- ACTIVE state,
- MCU_ONLY state,
- RETENTION state, with or without DDR and/or GPIO retention.
Depending on the current operational mode, some voltage domains
remain energized while others can be off.
This PFSM is also used to trigger a firmware update, and provides
R/W access to device registers.
What userspace code uses these new ioctls? Do you have a pointer to it
anywhere?
I will provide a user app in 'samples' directory in v6.
--- /dev/null
+++ b/include/uapi/linux/tps6594_pfsm.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Userspace ABI for TPS6594 PMIC Pre-configurable Finite State Machine
+ *
+ * Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/
+ */
+
+#ifndef __TPS6594_PFSM_H
+#define __TPS6594_PFSM_H
+
+#include <linux/const.h>
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/* PFSM state definitions */
+enum pfsm_state {
+ PMIC_ACTIVE_STATE,
+ PMIC_MCU_ONLY_STATE,
+ PMIC_RETENTION_STATE
+};
+
+/**
+ * struct pmic_state - PMIC state identification
+ * @state: PFSM destination state
+ * @options: options for destination state
+ */
+struct pmic_state {
+ enum pfsm_state state;
+ __u8 options;
+};
+
+/* Commands */
+#define PMIC_BASE 'P'
+
+#define PMIC_GOTO_STANDBY _IO(PMIC_BASE, 0)
+#define PMIC_GOTO_LP_STANDBY _IO(PMIC_BASE, 1)
+#define PMIC_UPDATE_PGM _IO(PMIC_BASE, 2)
+#define PMIC_SET_STATE _IOW(PMIC_BASE, 3, struct pmic_state)
+
+/* Options for destination state */
+#define PMIC_GPIO_RETENTION _BITUL(0)
+#define PMIC_DDR_RETENTION _BITUL(1)
+#define PMIC_MCU_ONLY_STARTUP_DEST _BITUL(2)
Please read Documentation/driver-api/ioctl.rst which says:
* Bitfields and enums generally work as one would expect them to,
but some properties of them are implementation-defined, so it is
better to avoid them completely in ioctl interfaces.
For a brand-new ioctl interface, you did both of these unrecommended
things. Why set yourself for complexity when you do not need to?
I will fix that. Thank you for your feedback.
Julien
