Merge tag 'i2c-host-6.13-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-mergewindow

i2c-host updates for v6.13, part 1

Major Improvements and Refactoring:

 - All controllers using the 'remove_new' callback have been
   reverted to use the 'remove' callback.

 - Intel SCH controller underwent significant refactoring,
   this brings love and a modern look to the driver.

 - PIIX4 driver refactored to enable usage by other drivers
   (e.g., AMD ASF).

 - iMX/MXC improved message handling to reduce protocol overhead:
     Refactored DMA/non-DMA read/write and bus polling mechanisms
     to achieve this.

 - ACPI documentation for PIIX4.

New Features:

 - i2c-cadence added support for atomic transfers.
 - Qualcomm CII added support for a 32MHz serial engine clock.

Deprecated Features:

 - Dropped outdated support for AMD756 S4882 and NFORCE2 S4985. If
   somebody misses this, Jean will rewrite support using the proper
   i2c mux framework.

New Hardware Support:

 - Added support for:
   - Intel Panther Lake (new ID)
   - AMD ASF (new driver)
   - S32G2/S32G3 SoCs (new ID)
   - Realtek RTL I2C Controller (new driver)
   - HJMC01 DesignWare ACPI HID (new ID)
   - PIC64GX to Microchip Core (new ID)
   - Qualcomm SDM670 to Qualcomm CCI (new ID)

1 files changed, 22 insertions, 15 deletions

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index b73b3aa92f3f..5c0cc7aae872 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -671,10 +671,6 @@ static int pcc_data_alloc(int pcc_ss_id)
  *  )
  */
 
-#ifndef arch_init_invariance_cppc
-static inline void arch_init_invariance_cppc(void) { }
-#endif
-
 /**
  * acpi_cppc_processor_probe - Search for per CPU _CPC objects.
  * @pr: Ptr to acpi_processor containing this CPU's logical ID.
@@ -867,7 +863,7 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 
 	/* Store CPU Logical ID */
 	cpc_ptr->cpu_id = pr->id;
-	spin_lock_init(&cpc_ptr->rmw_lock);
+	raw_spin_lock_init(&cpc_ptr->rmw_lock);
 
 	/* Parse PSD data for this CPU */
 	ret = acpi_get_psd(cpc_ptr, handle);
@@ -905,8 +901,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 		goto out_free;
 	}
 
-	arch_init_invariance_cppc();
-
 	kfree(output.pointer);
 	return 0;
 
@@ -1087,6 +1081,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val)
 	int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu);
 	struct cpc_reg *reg = &reg_res->cpc_entry.reg;
 	struct cpc_desc *cpc_desc;
+	unsigned long flags;
 
 	size = GET_BIT_WIDTH(reg);
 
@@ -1126,7 +1121,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val)
 			return -ENODEV;
 		}
 
-		spin_lock(&cpc_desc->rmw_lock);
+		raw_spin_lock_irqsave(&cpc_desc->rmw_lock, flags);
 		switch (size) {
 		case 8:
 			prev_val = readb_relaxed(vaddr);
@@ -1141,7 +1136,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val)
 			prev_val = readq_relaxed(vaddr);
 			break;
 		default:
-			spin_unlock(&cpc_desc->rmw_lock);
+			raw_spin_unlock_irqrestore(&cpc_desc->rmw_lock, flags);
 			return -EFAULT;
 		}
 		val = MASK_VAL_WRITE(reg, prev_val, val);
@@ -1174,7 +1169,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val)
 	}
 
 	if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
-		spin_unlock(&cpc_desc->rmw_lock);
+		raw_spin_unlock_irqrestore(&cpc_desc->rmw_lock, flags);
 
 	return ret_val;
 }
@@ -1916,9 +1911,15 @@ unsigned int cppc_perf_to_khz(struct cppc_perf_caps *caps, unsigned int perf)
 	u64 mul, div;
 
 	if (caps->lowest_freq && caps->nominal_freq) {
-		mul = caps->nominal_freq - caps->lowest_freq;
+		/* Avoid special case when nominal_freq is equal to lowest_freq */
+		if (caps->lowest_freq == caps->nominal_freq) {
+			mul = caps->nominal_freq;
+			div = caps->nominal_perf;
+		} else {
+			mul = caps->nominal_freq - caps->lowest_freq;
+			div = caps->nominal_perf - caps->lowest_perf;
+		}
 		mul *= KHZ_PER_MHZ;
-		div = caps->nominal_perf - caps->lowest_perf;
 		offset = caps->nominal_freq * KHZ_PER_MHZ -
 			 div64_u64(caps->nominal_perf * mul, div);
 	} else {
@@ -1939,11 +1940,17 @@ unsigned int cppc_khz_to_perf(struct cppc_perf_caps *caps, unsigned int freq)
 {
 	s64 retval, offset = 0;
 	static u64 max_khz;
-	u64  mul, div;
+	u64 mul, div;
 
 	if (caps->lowest_freq && caps->nominal_freq) {
-		mul = caps->nominal_perf - caps->lowest_perf;
-		div = caps->nominal_freq - caps->lowest_freq;
+		/* Avoid special case when nominal_freq is equal to lowest_freq */
+		if (caps->lowest_freq == caps->nominal_freq) {
+			mul = caps->nominal_perf;
+			div = caps->nominal_freq;
+		} else {
+			mul = caps->nominal_perf - caps->lowest_perf;
+			div = caps->nominal_freq - caps->lowest_freq;
+		}
 		/*
 		 * We don't need to convert to kHz for computing offset and can
 		 * directly use nominal_freq and lowest_freq as the div64_u64